Five of game's best have something to prove in spring training

Needs to Prove: He's not done

In his first 10 major league seasons, Suzuki hit .331/.376/.430 and not just won, but earned 10 Gold Gloves. During that decade, his single-season lows in the three slash stats were a .303 batting average, .350 on-base percentage and .386 slugging percentage. Last year, in his age-37 season, Ichiro hit .272/.310/.335. What's more, the major advanced fielding metrics (plus/minus, Total Zone, Fielding Runs Above Average and Ultimate Zone Rating) were unanimous in the opinion that Suzuki's play in rightfield had fallen off considerably. The result was a season in which Ichiro, a future Hall of Famer on both sides of the Pacific and one of the signature players of the last decade, was no better than a replacement level rightfielder. Given that he wasn't hurt last year, the easiest explanation for his apparent collapse was age.

However, Ichiro's 40 stolen bases at an 85 percent success rate last year, both better than his average over the previous 10 years, contradict the suggestion that he is slowing down. It's possible that after a decade of remarkable consistency that defied the odds by depending so heavily on the typically fickle batting average, Ichiro finally had an off year, and nothing more. His nearly 60-point drop in batting average on balls in play would seem to concur, but the ratio of skill-to-luck in hitters' BABIPs is much higher than in pitchers'.

Suzuki is such a unique player that it seems foolish to make any assumptions about what this season will bring, though one wonders if the Mariners decision to move him from leadoff to third in the batting order is going to do anything other than give him another reason to tinker with his approach. No matter, now 38 and entering the final year of his contract, Suzuki suddenly has a lot to prove.

Needs to Prove: He can stay healthy, remain behind the plate and hit for power, particularly at home

Mauer hit .327/.407/.481 in his first six-plus major league seasons, averaging 134 games played from 2005 to 2010, but last year he was healthy enough to appear in just 82 games and hit a punchless .287/.360/.368 with just three home runs. Mauer is no stranger to injury, but coming off surgery to address irritation caused by the plica band in his left knee last season, he would up missing 57 games from mid-April through mid-June due to bilateral leg fatigue and his season ended in mid-September because of pneumonia.

Mauer did hit .312/.390/.405 over his final 269 plate appearances from June 25 through the end of his season, but there's still very little power in that line (an isolated power -- slugging percentage minus batting average -- of .093 compared to the .154 in the multi-season line at the start of this paragraph). The weakness in Mauer's legs would seem an obvious source of his power outage last year, but his new ballpark isn't helping. Over the last two seasons, Mauer has slugged .478 on the road, but 94 points lower, a mere .384, at Target Field. In 457 plate appearances at home over those two season, Mauer has homered just once at the Twins' new ballpark.

If that wasn't enough of a concern, after he returned from his first-half disabled list stay last year, Mauer started behind the plate on three consecutive days just twice over the entire remainder of the season, going just 1-for-16 over the one stretch during which he started at catcher four days in a row, and just two of his final 15 starts on the season came behind the plate (five were at first base, eight at designated hitter).

Mauer at his best is a great hitter who would be valuable at any position, but it's clear that both his ability to catch and his abilities as a catcher greatly increase his value. If he has to move off the position, his production at the plate becomes a much larger component of his overall value, and if his power doesn't move with him, he could go from being one of the best players in the game to being a decidedly ordinary one. That's a disastrous outcome for the Twins, who owe the former AL MVP and hometown hero $161 million over the next seven seasons, through 2018.

Needs to Prove: He can hit for something other than power

Wells' problem at the plate is the exact inverse of Mauer's. The only thing he did well with the bat last year is drive the ball. Wells hit 25 homers in 529 plate appearances, good for a .194 isolated slugging, which was right in line with his career rate. However, he also posted an on-base percentage of just .248, which was the worst by a hitter who qualified for the batting title since Matt Walbeck's .246 in the strike year of 1994. In fact, since 1920, only 14 qualified batters have reached base less in than a quarter of their plate appearances, only 11 have reached base less often than Wells did last year and every single one of those men was a middle infielder or catcher. Wells is the only corner man in the bunch.

A career-low .218 batting average, precipitated by a miserable .214 BABIP, played a large role in Wells' misfortune, but that wasn't just bad luck. Wells hit nearly everything in the air last year, and while that helped produce his 25 homers, a full quarter of his fly balls didn't leave the infield. In addition, his line drive rate was nearly half the league average, he struck out more often than he ever had before and he walked less often -- just once every 26.5 plate appearances. Over the last five seasons, Wells has hit a roughly league-average .258/.308/.443, but he's never been average. Instead he has alternated two strong seasons with three awful ones in which he was roughly 15 percent worse than average by OPS+, which is adjusted for ballpark.

Wells was an asset in the field last year, which is not a small thing given the success enjoyed by the Angels fly-ball-oriented pitchers, including Jered Weaver and Dan Haren, but the man threatening to take his job, top prospect Mike Trout, should be even better. The $63 million the Angels still owe Wells over the next three years will guarantee him a fair shot at keeping his job, but the Angels didn't let that money stop them from investing heavily in Albert Pujols and C.J. Wilson, and if Wells can't prove that 2011 was a fluke, I don't expect the Angels will let it stop them from treating Wells as a sunk cost the way they did Gary Matthews Jr. over the final three years of his ill-advised deal.

Needs to Prove: He's healthy and can still produce at the plate

In his 20s, Rolen hit .286/.378/.520 with 226 home runs and earned six Gold Gloves, but a pair of labrum surgeries in his left shoulder in his age-30 season caused his career to jump the Hall of Fame track. He has hit just .277/.347/.452 in his 30s with just 82 more homers while averaging just 107 games a year and having two more surgeries on that left shoulder, the most recent coming in August, ending his 2011 season after only 65 games played. That doesn't seem to leave room for Rolen, who will be 37 in early April, to prove he has anything left to offer, but before his miserable (.242/.279/.397), injury-shortened 2011 season, he seemed to be on the comeback trail, showing steady improvement through his All-Star and Gold Glove-winning 2010 season in which he hit .286/.358/.497 with 20 homers and helped lead the Reds to their first playoff appearance since 1995.

The Reds are hoping that Rolen's surgery will do the trick, because with the Brewers weakened by the Prince Fielder's departure and, perhaps, Ryan Braun's suspension, another playoff berth is within reach if they can get a solid contribution from third base. However, if Rolen, who is in the final year of his contract, isn't going to be the man to make that contribution, the Reds have utility man Todd Frazier and slugger Juan Francisco (.304/.337/.559 in 742 career plate appearances at Triple-A) available to man the position, possibly as a lefty-righty platoon.

Needs to Prove: He's a viable major league starting pitcher

Talk about having something to prove. The Yankees just paid the Pirates $20 million to take Burnett in exchange for two non-prospects, preferring to have Freddy Garcia, a 35-year-old who no longer hits 90 miles per hour on the radar gun and hasn't qualified for an ERA title since 2006, and Phil Hughes, a 25-year-old who posted a 5.79 ERA in just 74 2/3 innings last year due to mysterious arm problems, duke it out for Burnett's rotation spot.

It was the right move. Over the last two seasons, Burnett went 21-26 with a 5.20 ERA and 1.47 WHIP. The only pitcher in baseball over the last two seasons with more than 330 innings pitched and an ERA+ lower than Burnett's 84 (100 is average) was John Lackey, a comparable disaster on an identical contract with the Red Sox who will miss the entire 2012 season following Tommy John surgery. Burnett made 65 starts for the Yankees over the last two seasons and just 24 of them were quality. No other pitcher with more than 50 starts over the last two seasons had a quality start percentage below 40; Burnett's was 37 percent.

It wasn't difficult to foresee disaster when the Yankees signed Burnett to a five-year, $82.5 million deal prior to the 2009 season, but I thought Burnett would be an average starter who had trouble staying healthy. Instead, Burnett missed just one start in three years with the Yankees, but went from being a fairly average pitcher in '09 to the worst full-time starter in baseball in 2010 and '11.

In joining the Pirates, he escapes both the DH league and the stacked American League East, and will instead get to face opposing pitchers at the plate and pitch in a largely de-fanged division that just lost Fielder and Pujols, could be without Braun for two months,and includes an Astros team that is fielding a Triple-A lineup. The opportunity is there for Burnett to salvage his career as a starter, but the $13 million the Pirates are paying him, though it makes him their most expensive player, won't provide him with as long a leash as he had in New York. It's also worth remembering that even before he came to New York, Burnett was never one of the league's better pitchers.