It is certain that the Twins' Opening Day roster will contain five starting pitchers. It's anyone's guess, though, which five pitchers will be thus honored. In order to keep you up to speed, then, here's a guide to all of the pitchers under consideration.

Isn't he the one that: Diamond was the team's only half-decent starter in 2012, posting a 3.54 ERA in 27 starts in the big leagues.

The Twins aren't talking about: Diamond threw 207.2 innings last year between Rochester and Minnesota, his first 200+ IP season, and got significantly tired down the stretch, posting a below-average 4.44 ERA after August 1.

Nationality: Canadian

We're guessing he won't be in the Opening Day rotation because: He had surgery to remove a bone chip from his elbow in mid-December. Though we have no evidence they were involved, we're still going to blame the Twins medical staff and their "Rest And Rehab For All Injuries Big And Small" plan.

Isn't he the one that: Came over from Philadelphia in the Ben Revere trade.

We're not talking about: Post All-Star Break last year, Worley was awful, posting a 5.04 ERA and just 29 strikeouts in 45 innings. (The part we're not talking about is how those strikeout numbers make him the Randy Johnson of the Twins rotation.)

Don't blame the park: In his career, Worley's allowed a higher OPS on the road (.740) than at the bandbox in Philly (.717).

We're guessing he won't be in the Opening Day rotation because: Worley had - you guessed it - bone chips in his elbow last year, which sent him to the disabled list in May and curtailed his season after he had surgery in early September. He says everything's fine. The Twins say everything's fine. (Their medical staff says: rest and rehab!) So I think we're all expecting that everything will not be fine, starting about March 25.

Isn't he the one that: Missed most of the Mets' 2012 season after undergoing Tommy John surgery at the end of April. Non-tendered by the Mets. Signed by the Twins for one year and $4 million.

The Twins aren't talking about: Despite what every pitcher believes, it generally takes 18 months, more or less, for the elbow to recover from Tommy John surgery. So Pelfrey should be ready to go by November!

Finally, someone who doesn't listen: The Mets wanted Pelfrey to have some procedure that involved injecting "platelet-rich blood" into his elbow instead of surgery. Pelfrey was smart enough to resist. (The Twins medical staff wanted, of course, rest and rehab.)

We're guessing he won't be in the Opening Day rotation because: Pelfrey has no doubt he'll be ready for Opening Day, thus making him our second candidate for everything going wrong on or about March 25.

Isn't he the one that: Signed by the Twins for 2 years and $10 million, or about one more year and $5 million more than he could possibly be worth.

The Twins aren't talking about: Correia's five years as a starting pitcher have all been mediocre or worse. In 2012, despite the Pirates staff being one of the National League's worst, Correia still got kicked out of the rotation mid-season in favor of Wandy Rodriguez.

Seriously: I can't even manage a joke about the Twins medical staff. Read Aaron Gleeman go off on the guy here and here.

We're guessing he won't be in the Opening Day rotation because: Mentally and emotionally devastated after the clubhouse staff accidentally puts a "MARQUIS" jersey in his locker by mistake.

Isn't he the one that: The Twins first-round pick in 2009, he was a Top-100 prospect in both 2010 and 2011, but now he's still working his way back from Tommy John surgery in November 2011.

The Twins aren't talking about: Gibson struggled with elbow soreness in mid 2011. After flying to Minneapolis in August to be examined by team doctors, the Twins recommended - wait for it - rest and rehab. This went very poorly and effectively just wasted three months before Gibson had surgery in November.

Falling down in the Fall League: In Gibson's first three starts in last year's Arizona Fall League, his return to the mound, he struck out 19 in 13 innings while allowing just one run. In his last three, he allowed 13 runs in just over ten innings, for an ugly 11.32 ERA.

We're guessing he won't be in the Opening Day rotation because: Well, he's never pitched in the big leagues, and is coming off reconstructive arm surgery and thus will probably be on an innings limit anyway.

Isn't he the one that: Had excellent numbers between 2005 and 2008 for the A's and the Cubs, but made just 57 starts in those four years due to injury. Twins signed him to a minor-league contract with an invite to spring training.

The Twins aren't talking about: Harden hasn't pitched well since 2008, hasn't even risen to the level of "mediocre" since 2009, and hasn't pitched at all since 2011.

Nationality: Canadian

We're guessing he won't be in the Opening Day rotation because: If he's both healthy and good in the spring, it'll be going against ten years of evidence.

Isn't he the one that: Took 18 starts, in late 2011 and 2012, to finally get a major-league victory. But he's Australian and has a fun accent.

The Twins aren't talking about: Hendriks, much. Had we seen only his 2012 AAA numbers (9-3, 2.20 ERA, 106 IP), everybody would be falling all over themselves about Hendriks, but going 1-8 with a 5.59 ERA in the majors tends to weigh on the mind.

Taking the ball: Hendriks did make 32 starts and pitch 185 innings last year, between the minors and the majors, and even more importantly he hasn't had surgery of any kind since 2008, which makes him just about unique on the Twins roster. We take back this part, he had bone chips removed in November. So he's a doubt too, and you know what that means: rest and rehab!

We're guessing he won't be in the Opening Day rotation because: Everybody's seen enough.

Isn't he the one that: An Eden Prairie native, De Vries was probably the second-best starting pitcher in the Twins' rotation last year.

The Twins aren't talking about: How little that says.

The major-league level: De Vries actually had better numbers in the majors last year (5-5, 4.11 ERA) than he did at Triple-A (3-5, 4.37 ERA).

We're guessing he won't be in the Opening Day rotation because: Despite being arguably the team's second-best major-league starter, you could make a case that he was Rochester's fifth-best starter last year.

Isn't he the one that: Made you claw out your own eyeballs in anger (7.39 ERA, 23 HR allowed in 98 IP last year)

The Twins aren't talking about: He's making $5.5 million this year.

But he's not on the roster! Blackburn was removed from the 40-man roster, in exactly the same way as one would remove a dog turd from a sneaker.

We're guessing he won't be in the Opening Day rotation because: He's terrible. But don't count him out just yet. The Twins wouldn't mind getting some kind of value out of him, and having him mope around in Triple-A doesn't help anybody. If there's enough sore arms come opening day, and it looks like there will be, it wouldn't surprise me that much to see Blackburn back on the mound and the opposition smashing the ball over the fence like usual.

Isn't he the one that: Made 15 starts. Had no idea where the ball was going when it left his hand. Walked 53 in 79 innings, which is awful.

The Twins aren't talking about: Him. He's not on the 40-man roster, but elected to sign a minor-league deal even though he could have been a free agent, because if you're gonna make a major-league rotation, the Twins are probably your best chance.

Then how's he going to get back into the rotation? The same way Blackburn might, and the same way he did last year - through the back door and against all odds.

We're guessing he won't be in the Opening Day rotation. Period. But hey, it could happen.