It’s hard to believe, but Major League Baseball’s Opening Day is now only three weeks away, and fans are starting to get pumped. Last week we took a look at some of the game’s aging stars who should just forget forget about one more comeback and retire already. So today we take a look at the other side of the coin: players who desperately need and are capable of big comebacks this year.

Now, some of the guys on this list need a comeback from injury. Others need a comeback from a year-long funk. But whatever the reason, each one of them needs to prove that they still got it—for their sake, and for the sake of their teams.

Let’s get started.

When the Mets picked up Johan Santana from the Twins prior to the 2008 season, they thought they were getting a 2x Cy Young winner and the best pitcher in baseball. And for one season, that is indeed what they got, as Johan went 16-7 with a league-leading 2.53 ERA and 234 innings pitched in 2008. Since then, the guy has pitched well, he just hasn’t pitched often. He missed parts of 2009 and 2010, then all of 2011 with a shoulder injury. This year Santana is 32, so there should be a little gas left in the tank, but he and the Mets need a comeback big time.

Last season, his first with the Angels, Vernon Wells got paid $26 million to hit .218/.248/.660, with an OPS+ of 83 (17 points below “average”) and -0.3 WAR (wins above replacement). Ouch. He was probably the second-worst everyday player in the majors.

Nevertheless, he did hit 25 home runs, and it’s been reported that Vernon has worked with private coaches to rework his swing this year. So there is a chance the Angels’ pricey outfielder can make a good comeback. He’s made a decent comeback before, back in 2010 with the Jays.

Is there anyway he can actually be worth $26 million? No, probably not. But he can certainly minimize the Angels’ loss.

It’s not easy for a ballplayer to have an historically bad season. You know why? Because they usually get sent packing if they stink too much. However, teams just don’t waive guys making $12 million. So Adam Dunn got a lot of plate appearances last year for a guy hitting .159/.292/.277.

But here’s the thing: prior to last year, the guy had shown no signs of slowing down. In 2010, just like every year since 2004, Adam Dunn hit 38 HRs, batted .260/.356/.546, and had an OPS+ of 138. He was a metronome.

So the question is, did he just hit a wall in 2011? Was that the end? My guess is no. The steroids era made us forget how quickly players decline, but they still don’t usually decline that fast. So I’m thinking last year was just a blip, and Dunn bounces back to have a respectable year for the White Sox.

Aaron Hill has been a mystery, wrapped in a riddle, buried in an enigma.

He was the Blue Jays second basemen of the future, on track for greatness. Then he suffered a nasty concussion that sidelined him for most of 2008. Okay, not his fault. Then he made an historic comeback in 2009, playing stellar defense and hitting .286/.330/.499 with 36 HRs and 108 RBIs. Fantastic! He had finally arrived and fulfilled his potential! Except that the very next season, Hill hit .205/.271/.394, going from 5.1 WAR in 2009 to only 1.1 in 2010.

In 2011, he was well on his way to another disappointing season with the Jays when he was traded to the Diamondbacks. And it seems the change of scenery did him good. In 33 games, he hit .315/.386/.492. The guy will only be 30 years old this season, so the Diamondbacks are really hoping a full season in the desert helps him regain his form.

Twins first basemen Justin Morneau was a perennial MVP candidate through 2009. In fact, he was the AL MVP in 2006, and he finished second in 2008. But the last two seasons have been plagued by injury, with the Canadian slugger limited to only 150 games in those years. With the AL Central being up for grabs every season*, it’s really imperative that Morneau have a big comeback season for the Twins. His presence can make or break the club.

*Yeah, yeah, I know. The Tigers got Prince Fielder this year. But you know who’s playing the hot corner now? Cabrera. That’s gonna cost them a few runs. So I wouldn’t concede the division title just yet.

2007 NL Cy Young winner Jake Peavy is never going to post the kind of numbers pitching at Chicago’s U.S. Cellular Field as he did pitching at San Diego’s PETCO Park. No pitcher could. The Cell is a matchbox and PETCO is like the Grand Canyon. But he can still be a force to be reckoned with…if he can stay healthy.

Over the last three seasons, the guy has averaged only 106 innings pitched while getting paid at least $15 million. After the 2012 season, in which he will make $17 million, the Sox can either pick up his option for $22 million or choose a $4 million buy out. So if Peavy wants to get those ginormous paychecks next year, he’d better stay healthy and effective this season.

Cardinals ace Adam Wainwright was at or near the top of the league in every major pitching stat in 2009 and 2010, finishing 3rd and 2nd in Cy Young voting respectively. But he had to sit out the entire 2011 season after having Tommy John surgery last spring. The Cardinals still managed to win the World Series without him (though he was with the team in the dugout all season), but this year will be a little different—maybe you’ve heard that the Redbirds lost a pretty good first basemen back in December?

So, yeah, without Albert Pujols, if the Cardinals want to stay competitive, they’re going to need a huge comeback season from Adam Wainwright.

When the Red Sox snatched Carl Crawford away from the Rays after the 2010 season by signing the free agent to a massive 7-year $142 million deal, they assumed they were getting a guy with an OPS+ of 135 and worth 6.1 wins above replacement. Instead, in 2011, Crawford had and OPS+ of 85 and was worth only 0.0 wins above replacement. Yikes.

Crawford may not care how he does this season, because he’ll be earning $19.5 million regardless, but I’m sure the Red Sox would really love to avoid disappointing season that ends in September instead of October.

Incidentally, Crawford, a guy known for his speed, will be paid $21 million in 2017…when he is 35 years old. And the Cubs made Theo Epstein their new team president. You gotta love it.

In his rookie season in 2010, all Buster Posey did was hit .305/.357/.505 and help lead the Giants to their first World Series Championship in 52 years (and their first since moving to San Francisco). So when Posey broke his leg in a gruesome home plate collision last May, forcing him to sit out for the rest of the 2011 season, that was pretty much it for the offensively challenged defending champs.

So this season, Buster Posey needs a comeback not only to re-establish himself as one of the game’s premier up-and-coming stars, but also to bring the Giants back into contention.

Joe Mauer is one of the best 2 or 3 pure hitters in baseball today…when he’s healthy. The problem is that he is also a catcher with bad legs. And when the legs are weak you can’t drive the ball. In 2010, Mauer hit for average and got on base a lot (.327 and .402), but his power was depleted (only 9 HRs and a .469 slugging percentage). Then, last season, Joe only had 333 plate appearances and a .368 slugging percentage.

Mauer’s record-setting (for a catcher) 8-year $184 million deal runs from 2011 through 2018. Both he and the Twins need a big comeback, or aint nobody gonna be having any fun at Target Field for the next 7 years.

A couple fo years ago, people were actually wondering whether Ramirez could give Albert Pujols a run for his money in the contest for the title, “Best Player in Baseball.” And the discussion was warranted, as Ramirez his .342/.410/.543 in 2009, with an OPS+ of 148 and a WAR of 6.8. But last year Ramirez was hampered by injury, and he only made 385 plate appearances, hitting .243/.333/.379.

The Marlins open a new state-of-the-art baseball only stadium this season, and to celebrate they made some huge signings in the offseason (Jose Reyes, Heath Bell, Jon Garland). If Hanley Ramirez can make a comeback and regain his MVP candidate form, the Marlins may not even need the new expanded playoffs format to get into October. They might actually give the Phillies a run for their money in the NL East.