To believe or not to believe, that is the question.

It's not completely out-of-the-ordinary for a mediocre pitcher to dominate for short periods of time. Heck, even Carlos Silva shut down the Houston Astros last week. The important question is: Do you believe a hot pitcher will keep it up?

Here's some background on a few of the hotter starters, so you can decide to believe or leave:

Kevin Correia, Padres -- Correia didn't come completely out of thin air ... he had a 3.81 Fielder Independent Pitching (FIP) rate over 198 innings last year. However, his April 17 start (5.2 innings, three hits, no runs, and eight strikeouts) has people buzzing. Does he deserve the buzz? In a word, maybe.

He's been very inconsistent so far in 2010. He allowed three homers in his first start, and then walked more than he struck out in his second start.

Correia was at his best in '06, when he had a 7.36 K/9, 2.84 BB/9 and 2.59 K/BB. He produced a 3.52 FIP in 69.2 innings that season.

Those '06 numbers are his upside and they would certainly be helpful in fantasy leagues. Wait and see if he can build on his April 17 start and be more consistent.

Ricky Romero, Blue Jays -- Romero was solid last season (4.33 FIP, 7.13 K/9) and has been flat-out dominant this year. Is this a trend or hot streak?

It looks like a trend for now, so long as he maintains his control. Romero's 8.61 K/9 isn't shocking considering what he did in '09, but it's his 2.35 BB/9 that shows real progress.

He walked 3.99 batters per nine innings last year and hasn't produced a rate below 3.00 for any length of time since '06 in the minors.

With a plus changeup and curve, Romero has the tools to be an excellent ground ball pitcher. Combine that with his solid strikeout ability, and you have someone who can really help fantasy teams if his walks are held in check.

Jaime Garcia, Cardinals -- With elbow problems behind him, the former top prospect is tearing things up to start '10. One red flag: His first strike percentage (FS%) is just 40.8. His 3.46 BB/9 is due for a jump if he is not able to get ahead of batters more often.

His GB% (69.7) skills are real, but his BABIP (.158), HR/9 (0.00) and average (.120) will all normalize soon. Ride the hot streak while it continues, then prepare for a rocky stretch.

Doug Fister, Mariners -- Even at his best (right now), Fister doesn't look like a dominating pitcher. His 4.26 K/9 and 91.9 contact percentage appear more like a pitcher that batters can square up on regularly. So what do you do with a pitcher who doesn't look good ... even when he looks good? You leave him on the free agent list.

Fister has good control, but that's about it. Keep him away from your fantasy rosters.

Mike Pelfrey, Mets -- Pelfrey has never been able to translate his minor-league K/9 abilities to the majors. For someone with poor/average control, a K/9 around 5.00 isn't going to work. The difference in '10 is that he's finally making progress with strikeouts. His K/9 isn't knocking anyone's socks off at 6.86, but it's all about baby steps.

He will allow home runs (current HR/9 is 0.00) moving forward and his .231 BABIP will inch toward his career .312 rate. As long as he his K/9 is around 6.50, he should be useful in fantasy leagues.

Dallas Braden, Athletics -- Braden is making big strides from his '09 season in both K/9 and BB/9. His K/BB in his first two major-league seasons was 1.64 and 1.93 and this season it's 5.33.

Braden's approach has been above average for the past two years in that he's getting ahead of batters at a good pace. His FS% was 62.1 last year and is 63 this year.

His contact rate improvement is harder to believe. His rate dropped from 83.7 last year to 76.7 so far this year. He's using his changeup more and his fastball less, maybe that's enough of a difference to account for the lower contact rate. He's likely in for a K/9 regression.

David Price, Rays -- Price has improved his K/9 and BB/9 from '09, which is certainly a great recipe for rapid improvement. He's playing with fire (low GB rate, lucky LOB rate), but few pitchers have as much talent. This could be his breakout.

Jonathan Sanchez, Giants -- Sanchez is like a more volatile Ubaldo Jimenez. He might vary greatly from start-to-start, but he'll always bring the strikeouts. After 10 more strikeouts on April 20, his K/9 is 12.57.

18.9%: Clayton Kershaw's O-Swing% (percentage of pitches swung at outside the zone), the lowest in the majors. Its clear batters are backing off of Kershaw's pitches because of his penchant for walks. He's talented enough to make up for it, but things should get easier once the walks decrease and batters start giving him credit for throwing strikes.

Up: Brad Penny, Cardinals -- Penny is the latest product of the St. Louis magic. His GB% is a career-high 54.1 and his BB/9 is 1.29. After Joel Pineiro had the same improvement for the full year in '09, there's no reason to think Penny can't carry his success through all of '10. His numbers won't stay quite this good (currently sporting a 2.18 FIP), but he should be solid enough to own in mixed leagues.

Up: Joel Pineiro, Cardinals -- Fantasy owners approached Pineiro like a rabid raccoon in drafts this offseason, but he's rewarding those owners brave enough to take the plunge.

His BB/9 and GB% numbers are right in line with '09 and appear to be his keys to success.

Down: Zack Greinke, Royals -- Greinke's FS% is just 45.0 so far this season, one of the lowest in baseball. That's led to a 3.06 BB/9, up from his excellent 2.00 last season.

Batters are also making much better contact against him. His HR/9 is 1.02 (0.43 in '09) and his average against is .286 (.232 in '09).

Greinke's '09 numbers are skewed a little bit because of his ridiculously good start, but he's better than he's pitched so far in '10.

Down: Chad Billinglsey, Dodgers -- Billingsley now has two bad starts in three outings in '10. It looks like his poor end to '09 is carrying over into '0. The one positive is that he didn't walk anyone during his last start.

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