DETROIT -

The last two weeks marked an awful stretch for the Detroit Tigers' pitching staff, as a 3-8 record since May 19 has seen Detroit surrender an average of 7.1 runs per game.

Surprisingly, the culprit of the losing streak was the starting pitching, which has been a strength for the Tigers during a span of reaching the American League Championship Series three years in a row. Detroit starters notched just two quality starts during the 11-game stretch (both by Anibal Sanchez), and surrendered five or more runs seven times.

Despite the recent struggles, four of the Tiger pitchers have shown flashes of greatness throughout the last 14 months, whether it was Max Scherzer winning the Cy Young Award or Justin Verlander dominating the Oakland Athletics in the ALDS.

Though Scherzer, Verlander, Sanchez and Rick Porcello have all cemented themselves as quality starting pitchers, which one of them is the best?

As Detroit enjoys the top record in the AL through 50 games, here is the case for all four righties, keeping in mind their performances from last season, the 2013 playoffs and the first stages of 2014. Last season's statistics will provide the most recent sample of each pitcher's performance over an entire season, while the playoff numbers demonstrate their best efforts when the games matter most.

Justin Verlander

The title of "ace" in Detroit is Verlander's to lose. With a career ERA of 3.43 and 142 wins as a Tiger, Verlander has maintained his place atop the pitching staff by starting on Opening Day for seven straight seasons. The 31-year-old not only brought a Cy Young Award to the city of Detroit, but also the first MVP for a pitcher since 1992.

Verlander's track record is undeniably the best in the Tigers' rotation, but his regression over the past two years has been alarming for a club that recently signed him to a 10-year, $219.5 million contract.

2013: 13-12 record, 3.46 Earned Run Average, 218.1 innings pitched, 217 strikeouts

Last season began a stretch in which Verlander no longer looked like the pitcher who won the MVP Award in 2011. After pitching well through the month of April, an eight-run blasting at the hands of the Rangers on May 16 seemingly threw Verlander off his groove. He allowed five or more runs five times in the three months after that start, and finished with his worst ERA, fewest wins and fewest strikeouts since 2008.

2013 Playoffs: 1-1, 1.13 ERA, 23 IP, 31 SO

When the postseason began, the Tigers went with Scherzer to pitch Game 1 of the ALDS, but Verlander ultimately pitched like the ace in Game 2 by holding the A's scoreless in seven innings. For his sequel, the veteran took the mound in Game 5 when the Tigers were desperate for a win and threw eight two-hit innings with 10 strikeouts in Detroit's 3-0 win.

Even in the series loss to the Boston Red Sox, when the Tigers were eliminated from the postseason, Verlander dominated in his only start. He allowed his only run of the playoffs on a seventh-inning home run to Mike Napoli, and finished with 10 strikeouts in eight innings.

Verlander showed that he can still be the best pitcher in baseball when the occasion demands it, as he surrendered just 10 hits in 23 postseason innings. Brad Ausmus knows he can count on Verlander to be a workhorse, as he threw an average of 116 pitches in those three starts.

2014: 5-4, 4.04 ERA, 71.1 IP, 50 SO

Perhaps the most alarming aspect of Verlander's struggles is that the carryover into 2014 turns 2013's "anomaly" into a trend. Verlander's strikeouts have noticeably decreased from this time a year ago, when he fanned 82 hitters through his first 11 starts. He has yet to showcase a dominant performance, allowing two or more runs in each start but one, when he lasted just five innings while shutting out the Indians.

Fans around Detroit panicked last season when Verlander struggled, but he still managed to record seven starts of six or more shutout innings. In 2014, the former MVP is on pace for zero.

Max Scherzer

While Verlander experienced setbacks throughout 2013, Scherzer was enjoying a breakout year in which he took home the AL Cy Young Award. 2014 holds major implications for the 29-year-old's future as he tries to show that he can maintain that level of dominance.

2013: 21-3, 2.90 ERA, 214.1 IP, 240 SO

There was little dispute over who was the best pitcher in the AL last season, as Scherzer led the league in wins and posted career bests in ERA, WHIP, strikeouts and innings pitched. Scherzer decreased his ERA and WHIP for the third straight season and became the most important pitcher on the Tiger staff in wake of Verlander's down year. The electric right-hander has every opportunity to name himself the ace of the staff with a repeat performance in 2014, but one strong season isn't enough to dethrone a consistent contributor like Verlander.

2013 Playoffs: 2-1, 2.82 ERA, 22.1 IP, 34 SO

The faith that manager Jim Leyland developed in Scherzer was apparent when he called on him in relief during Game 4 of the ALDS with the Tigers on the brink of elimination. One of the greatest images of the postseason was Scherzer celebrating after escaping a bases-loaded no-outs jam en route to a victory that kept Detroit alive. Scherzer was also great in his three October starts, picking up three quality starts and striking out 34 batters.

2014: 6-1, 3.00 ERA, 72 IP, 82 SO

Through nine starts Scherzer was probably the frontrunner to win another Cy Young Award, boasting a 1.83 ERA and six wins. But the righty has allowed 12 earned runs in his last two starts to balloon his ERA to an even 3.00 amidst a difficult stretch for the Detroit pitching staff.

If Scherzer finishes the season with numbers similar to those of 2013, he will earn the top spot in the Tiger rotation just in time to sign a huge contract wherever he ends up in the offseason.

Anibal Sanchez

Many of the Tiger starters have looked like aces over the past two seasons, but Sanchez undisputedly has the nastiest arsenal. With a fastball and changeup that move as much as anyone else's in baseball and a deadly slider that he can locate on a dime, Sanchez is the most dangerous pitcher on the staff based purely on stuff. The Venezuela native takes a backseat to the 1-2 punch of Verlander and Scherzer, but he has quietly built a strong resume since joining the Tigers late in 2012.

2013: 14-8, 2.57 ERA, 182 IP, 202 SO

Scherzer's Cy Young Award largely overshadowed the excellent work that Sanchez did during the 2013 season. After signing a five-year contract with Detroit, Sanchez posted the best ERA in the AL at 2.57 and was among the top 10 in wins, strikeouts, WHIP and WAR. He allowed more than three runs just five times and nearly threw a no-hitter against the Twins. His most electric performance of the season came on April 26, when Sanchez struck out 17 Braves in eight shutout innings.

2013 Playoffs: 1-2, 4.41 ERA, 16.1 IP, 23 SO

Sanchez struggled in his first postseason start of 2013, allowing five runs to the A's in Detroit's Game 3 loss. But when Leyland turned to his No. 3 starter to pitch the first game of the ALCS against Boston, Sanchez bounced back with six no-hit innings, striking out 12 Red Sox.

2014: 2-2, 2.49 ERA, 43.1 IP, 41 SO

Through eight starts Sanchez has shown that his 2013 season was no fluke. The 30-year-old owns the lowest ERA on the staff, allowed three runs only once and has yet to surrender his first home run. Sanchez was the lone pitcher to keep Detroit competitive during the recent losing streak, surrendering just three runs in 15.1 innings after returning from the disabled list. Since coming to Detroit from the Marlins two seasons ago, Sanchez has been one of the most difficult pitchers to beat in baseball.

Rick Porcello

Porcello's name might not belong among elite starters' just yet, but an incredible start to the 2014 season has put the 25-year-old on the fringes of the conversation for Tigers' ace. The youngster is in his sixth season with Detroit after making his debut as a 20-year-old in 2009, and is enjoying the best start of his career.

2013: 13-8, 4.32 ERA, 177 IP, 142 SO

2013 was a year of progress for Porcello, who not only recorded his first career complete game in September, but also greatly increased his strikeout numbers that were previously near the bottom of the league.

Along with his inflated strikeout total came an appreciation for Porcello's control, which put him at 12th in the AL with a 3.38 strikeout-to-walk ratio.

Poor defense really hurt Porcello during his first few years as a Tiger, as the groundball pitcher fell victim to one of the highest opponent batting averages on balls in play in the country. With an improved defensive team in 2014 the Tigers are getting a better look at what Porcello is really capable of.

2013 Playoffs: 0-1, 0.00 ERA, 0 IP, 0 SO

Leyland chose an interesting role for Porcello during the postseason, placing him in the back end of the bullpen. Unfortunately Porcello surrendered hits to all three batters he faced, proving that he was groomed to be a starter.

2014: 8-2, 3.82 ERA, 63.2 IP, 42 SO

At first glance, Porcello's inflated ERA gives his record the appearance of a fluke. But in his eight wins this season, the righty has allowed more than two runs just once, giving him six quality starts on the year. Porcello has often been a victim of abnormally poor starts that devastate his numbers, like his May 24 start in which he allowed eight earned runs. In order to become the ace of the rotation, Porcello will have to eliminate those starts and show consistent success throughout a campaign.

Who is the ace?

A simple solution to this question is to hand the label to Scherzer after he won the Cy Young Award and outperformed Verlander over the past 14 months. Leyland effectively offered Scherzer his rite of passage by handing him the ball for Game 1 of the playoffs last season, but Verlander regained the role on Opening Day.

The true conclusion lies in which statistics any one person believes to be most telling of an ace. Scherzer has 27 wins over the last two seasons, which is ultimately what matters to the team, but Sanchez consistently owns the top ERA on the team, which makes him the toughest pitcher to score against and least likely to have a disastrous outing.

Tigers fans are lucky to have so many quality options to consider, and the conversation about "Who is the Tigers' ace?" will likely drag on throughout the season. But through 50 games in 2014, only one Detroit pitcher ranks in the top 10 in the AL in ERA, wins, strikeouts and quality starts: The defending Cy Young Award winning Max Scherzer.