Santiago Casilla, Oakland

The age-gate scandal a couple years ago resulted in the then-Jairo Garcia aging three years and becoming far less of a prospect. Still, that hasn't prevented him from opening this year with 13 1/3 scoreless innings and an 18:2 K:BB. A pessimist would point to his 0.70 ERA through 25 2/3 innings last year and subsequent 8.28 ERA over his final 25 innings and advise caution, and that's exactly what I'll do. Still, the fact that he's also generating groundballs (1.50 G/F vs. last year's 0.70) is a positive sign. Casilla would be a prime candidate to step into the closer role should Huston Street get hurt or traded, though Joey Devine (0.96 ERA) and Andrew Brown (14 scoreless innings, but a 9:6 K:BB) are off to good starts as well. Then there's still Alan Embree hanging around.

Aquilino Lopez, Detroit

Denny Bautista set up Todd Jones' last save, but even though Bautista has a 1.59 ERA, his 7:9 K:BB is a concern. Sure, he throws hard enough to close, but would Jim Leyland really trust the erratic Bautista as his closer should Jones get hurt or otherwise lose his job? It's possible, since Leyland certainly trusts Jones despite his poor strikeout rate, but take a look at Lopez as a deep AL-only sleeper. He personifies the journeyman title, and at age 33, it's hard to see much upside here. Still, you have to focus on what he's done this year - one earned run in 18 1/3 innings with a 14:1 K:BB. He could see a few save opportunities should something happen to Jones before Joel Zumaya (shoulder) returns in July or August. Bautista looks to have a very slight edge over Lopez, but both are worth monitoring.

Jared Burton, Cincinnati

Burton had been lights out until a recent three-appearance stretch in which he surrendered four runs in 4 2/3 innings. Look beyond the inflated 3.97 ERA, however, and note this: 18:4 K:BB in 11 1/3 innings. That's a 14.3 K/9 ratio. He's also been a little unlucky on balls in play (.364 BABIP). Combine that with a 1.37 ERA after July 29 last year, and you have a nice young pitcher on the rise. He's replaced the injured David Weathers (elbow) as Francisco Cordero's top set-up man, and the way he's going, he'll probably keep that job once Weathers returns (early May). Cordero received a four-year, $46 million contract in the off-season, so he's going nowhere. However, you never know when the injury bug will strike.

Masahide Kobayashi, Cleveland

Manager Eric Wedge's comments this week that Kobayashi was "climbing up the ladder" should set off some bells for fantasy owners. He sports a 1.59 ERA through 11 1/3 innings, and, though he's not striking a lot of guys out (6:1 K:BB), he does have the best ERA among Cleveland relievers. He's no threat to Rafael Betancourt right now, but he might have passed Jensen Lewis and Rafael Perez in the pecking order, making the occasional save a possibility. It's difficult to imagine Joe Borowski reclaiming the closer job once he returns from his triceps injury. One scenario has Borowski in middle relief and the Indians preferring Betancourt in high-leverage situations in the seventh and eighth innings with Kobayashi closing the ninth.

Chad Qualls, Arizona

The man for whom Qualls was traded, Jose Valverde, has a 7.50 ERA as Houston's closer. Qualls, meanwhile, has yet to allow a run in 14 2/3 innings at a fraction of Valverde's $4.7 million salary. Chris Burke and Juan Gutierrez also came to Arizona in the deal, and while neither projects as a star, this deal looks like a win-win for Arizona. Tony Pena's probably still Brandon Lyon's top set-up man, though it's worth noting it was Qualls, not Pena, who got the call in the eighth on Monday. Keep an eye on which guy gets the ball in the eighth most often, as Lyon, despite his recent success, is always a candidate to go on a run that costs him the closer job. I'd like to see Qualls walk a few less batters (seven so far), but he's a reliever worth holding onto in deeper leagues.

Doug Brocail, Houston

It's been an ugly beginning to the season for Jose Valverde (7.50 ERA, four homers in 12 innings), and though he's been better lately with four straight scoreless appearances, it's still worth keeping an eye on Brocail. Brocail's firmly established himself as the eighth inning guy in Houston with a 3.46 ERA and 12:2 K:BB in 13 innings. The ERA is skewed quite a bit via one awful outing on April 22 (toss that one out and his ERA drops to 0.71). There's really nothing in his past (3.99 career ERA and 6.5 K/9) to suggest he'd be a viable long-term closer, but should the volative Valverde lose his job for a stretch, he could pick up a handful of saves.

Jesse Carlson, Toronto

B.J. Ryan entering Sunday's game at the start of the eighth inning with Toronto up 3-2 certainly raised a few eyebrows in the fantasy community. When Carlson then pitched the ninth to preserve a 5-2 win and notch his first save, we had to wonder about the Blue Jays' thought process. Would Ryan have pitched the ninth if it was a still a 3-2 game? Was manager John Gibbons simply trying to be smart and use his best reliever in a high-leverage situation? Who knows? But though Ryan is still the closer, this probably does mean Carlson has passed Jeremy Accardo (8.00 ERA) at least temporarily on the bullpen hierarchy. Carlson's been great (1.42 ERA, 15:2 K:BB in 12 2/3 innings), and he does have a 9.5 K/9 rate in 285 minor league appearances, so there's some talent here worth watching.

Leo Nunez, Kansas City

Nunez has spent parts of four seasons in the majors, and now, at age 24, seems to have settled in nicely as a late-inning reliever. He displayed a so-so strikeout rate (7.9 K/9), but he also doesn't walk a lot of hitters (2.4 BB/9) and has ranked among Kansas City's top prospects. He's started the eighth inning in Joakim Soria's last four saves. In one of those outings, Jimmy Gobble finished the eighth against a left-handed hitter. And in Nunez's last outing, he allowed a couple baserunners and had to be bailed out by Ramon Ramirez. Still, consider Nunez to be Soria's top set-up man, but also figure Ramirez and Gobble will be in the mix from time to time.

Guillermo Mota, Milwaukee

Derrick Turnbow's recent flukish save nothwithstanding (Mota had pitched the previous two days), it appears Mota has a leg up on the rest of the Milwaukee relievers to close should Eric Gagne wind up on the DL or otherwise lose the closer job. He's been pretty good for most of the year, though his line for his last two outings isn't helping my case. With a 14:10 K:BB and a 3.00 ERA, he's had some command issues, but David Riske (6.94 ERA) and Turnbow (7.94 ERA, 4:9 K:BB) don't appear to be options. Salomon Torres (2.08 ERA) and Mitch Stetter (6 2/3 scoreless innings, 9:3 K:BB) also have cases to close, but for now Mota's probably the best bet. (Just know my opinion could change any day.)

Duaner Sanchez, New York Mets

Billy Wagner's been the most dominant reliever in baseball so far (10 scoreless innings, one hit, and a 10:2 K:BB). Behind him, however, Aaron Heilman is sporting a 6.43 ERA, causing him to lose his job as Wagner's top set-up man. That role apparently now belongs to Sanchez, who after returning from a pair of shoulder surgeries that caused him to miss all of 2007, has been impressive this year (6 2/3 scoreless innings, just two hits, and a 4:2 K:BB). Watch how Willie Randolph uses his bullpen in the coming days and consider grabbing Sanchez in deep leagues.

Chris Perez, St. Louis

It's normally difficult to project minor league closers as slotting into the same role immediately upon being promoted to the big leagues, but Perez sure looks to be next in line for St. Louis. Jason Isringhausen is in the last year of his contract and is still an injury risk. He also has two losses in his last three appearances to go with an overall ERA of 6.55. Behind Isringhausen you have uninspiring options like Ryan Franklin and Randy Flores, so perhaps the opportunity will be there for Perez this year at some point. Pitching for Triple-A Memphis, he has a 2.31 ERA and six saves in 11 2/3 innings with a 12:4 K:BB. The four walks are noteworthy, as he struggled to a 6.8 BB/9 last year, so it's good to see the improved command. Track his progress.

The Texas Situation

C.J. Wilson's done a decent job as Texas' closer, saving 5-of-6 with a 1.80 ERA, though his 4:5 K:BB in 10 innings shows he's not exactly overwhelming opposing batters in the ninth. Still, he's in no danger, at least now, of losing his job. Beyond him, though, it gets dicey. Presumed closer-in-waiting Joaquin Benoit has a 6.75 ERA, Kazuo Fukumori lasted only four appearances before his 20.25 ERA punched his ticket to Triple-A and Eddie Guardado was hit hard in his last outing. So, who's next in line behind Wilson? Remember Franklyn German from the Tigers? He has a 0.79 ERA in 11 1/3 innings, though an 8:10 K:BB suggests an element of ERA risk. How about Jamey Wright (yes, THAT Jamey Wright)? He's been pretty good except for one horrible outing, but it's hard to imagine him closing games for even a Triple-A team. Wes Littleton, Josh Rupe and Scott Feldman are also there, but all have been just as terrible as Benoit. Consider this an unenthusiastic endorsement of German.

Merkin Valdez, San Francisco

Once one of baseball's better pitching prospects, Valdez has battled command issues and injuries, including Tommy John surgery in 2006, before re-emerging this season as a valuable member of the bullpen. Tyler Walker appears to still be Brian Wilson's primary set-up man, but neither are locks to maintain those roles going forward, and Valdez's stuff is better than both. If he can continue his excellent start (1.50 ERA), stay healthy and improve his command a touch (10:6 K:BB in 12 innings), things could open up for him later this year.

Next week, I'll channel my inner sabermetrician and look beyond some good (and poor) ERAs/W-L records to identify some pitchers primed for a rebound (or a fall).

Article first appeared 4/30/08