In the past weeks we have looked at pitchers who I am very optimistic about this year — I expect them to have a great season. We’ve also looked at the guys I just don’t have high hopes for at all. Now it’s time to look at the third group — the guys I have absolutely no idea about. Each of these guys has the clear potential to be very good — near the top of their league. They also have the potential to be a total nightmare for their teams, the fans, and bettors who choose to trust them.

It could go either way, and just thinking about them gives me a headache:

Roy Halladay, Philadelphia Phillies

In 2011 and for years before, Halladay was the best pitcher in baseball. He was totally terrifying — an absolute beast. Thanks to a shoulder injury last year he was first awful and then absent. If that was scary for fans and bettors then this spring has been the thing of nightmares. He has been totally ineffective despite reportedly being healthy, and his velocity is pedestrian — as low as 86 mph on his fastball according to reports. It would be easy to write off Halladay as a once-great pitcher who is now done. For a normal talent that would be fine, but there is nothing normal about what Halladay has done in his career. It’s tempting to believe that he can get back on track and dominate again. If he can find that old magic then he could provide some decent value early on. It’s very hard to know for sure what we will get from Halladay.

Jaime Garcia, St. Louis Cardinals

Garcia missed most of the summer last year, was spotty when he returned, and then he needed offseason shoulder surgery. Before that, though, Garcia was emerging as a very strong pitcher, and he’s on a solid team this year. He’s only 26, so it is tempting to trust him and assume he’ll be just fine. Shoulder surgery is scary, though, and you never really know if a pitcher will be the same guy when he returns. He has pitched well this spring, but it will take weeks for me to believe that he is healthy again and that he — and his shoulder — can be trusted.

Zack Greinke, L.A. Dodgers

You take a guy who has had some emotional problems in the past. You give him an impossibly huge contract and put him at the center of a media circus on a team that could be great or could crumble under the weight collective egos they are overpaying — just like it did last year. Then you add in a sore elbow over the spring. What could possibly go wrong? On Monday he faced the Royals in a Spring Training game and was totally useless against his former team — five runs on six hits. When Greinke is right he is as good as any pitcher out there — as the $147 million contract suggests. He has the ability to be his own worst enemy, though, and that is certainly a risk here. This could be a great season for the 2009 Cy Young winner or one that we will talk about forever — the type that makes Barry Zito look like a massive bargain.

Chris Sale, Chicago White Sox

Sale was impressive last year in his first full year as a starter. His 17-8 record and 3.05 ERA are impressive by any measure but especially so when you consider the team it came on. He obviously has talent and could easily take another step forward from what he did last year. Heck, even just treading water would make for an impressive season that would be valuable for bettors. My arm hurts every time he throws because of that odd arm action, though, so it is hard to trust him entirely to hold up for a full year or even part of it. Sale could become a true ace this year, or he could turn into that guy that trivia freaks will remember as that guy who had one good season a while ago.

Josh Beckett, Los Angeles Dodgers

This is the second Dodgers pitcher here on this list, and I could easily include Billingsley, too. It’s no wonder I am more than a little uneasy about this team despite their massive payroll. When Beckett is at his best he is a rare kind of power pitcher — a true talent. He’ll turn 33 in May, though, and he has a dozen years in his arm and more than his share of health issues. He could have a great year like we know he can have, or he can flounder like he did with Boston the first half of last year. He’s at the age and stage where a power pitcher has to become more of a command artist. I haven’t seen a lot of reasons over the years to believe he’ll make that transition smoothly, but I have been wrong before.

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