Another week, another front-runner to take a firm hold of the closer's role in St. Louis. The only difference is, the new man on top of the totem pole looks like he has a great chance to stay there. He headlines this week's waiver wire, along with a starting pitcher whose true value remains hidden this season and a cheap source of reliable power.

Fernando Salas, Cardinals -- The closing situation in St. Louis remains a mess, but Salas might be close to grabbing the job on a full-time basis. Tony LaRussa called on Salas in the top of the ninth of a tie game Tuesday, a typical assignment for a closer. Salas set the Phillies down in order, and the Cardinals rewarded him with a run and the win in the bottom half. Salas now sports a 1.02 ERA and 0.79 WHIP to go with 16 strikeouts in 17.2 innings this season. He's the guy to own in St. Louis and is favorable to a handful of pitchers getting saves right now, including Kevin Gregg and Frank Francisco.

Ervin Santana, Angels -- Thanks primarily to ugly glamour stats -- a 1-4 record and 4.85 ERA -- Santana is owned only in about 50 percent of fantasy leagues. If you focus solely on those numbers, it appears he has regressed from last season, when he went 17-10 with a 3.92 ERA. As as so often is the case, a look beyond those antiquated stats reveals the truth about his season. He's striking out more batters per nine innings (7.76 vs. 6.83) and walking fewer (2.43 vs. 2.95) with a better FIP (3.93 vs. 4.28). However, his BABIP is up to .301, seven points higher than his career average, and his strand rate is 65.3 percent, about five percentage points below league average. Both those numbers should correct themselves, providing better results for Santana. Jump in while you can.

Matt Joyce, Rays -- Given a chance to play regularly after the departure of Manny Ramirez, Joyce has finally started to fulfill the potential he showed when he slugged .492 as a 23-year old with the Tigers in 2008. Joyce is out to a .366/.429/.602 start this year, fueled by a 1.082 OPS against righties. The question with Joyce has always been his ability to hit lefties, and he has struggled in that regard in a small sample this season. Still, the Rays aren't exactly overflowing with reliable power hitters, and Joe Maddon does not have a reason to keep Joyce out of the lineup. He has an unsustainable .424 BABIP and is striking out more than 20 percent of the time, so the batting average is going to fall, but he should hit another 20 homers before the season is over. He should be owned in all formats.

Dustin Ackley, Mariners -- Second base remains as shallow as ever, but there is help on the horizon for struggling owners. The Mariners will likely call Ackley up from Triple-A Tacoma soon, and if you're in a league that restricts ownership of minor leaguers, this is a guy you want to pounce on as soon as he's up. After getting off to a slow start this season, Ackley is up to .280/.399/.445. He has never been thought of as a guy with a lot of power, but he has six homers in 200 plate appearances this season. He hit seven in all of 2010. They won't call him up to sit on the bench, so once he's in the majors he'll play a ton. Keep tabs on Ackley's progress and take a long look his way once he gets the call if you need a second baseman or middle infielder.

Justin Turner, Mets -- Did you just lose David Wright to a stress fracture in his back? Are you desperate for help at third base or second base? Are you in a very deep league (NL-only or more than 12-team mixed)? Then Turner is for you. With Wright out the next two weeks, Turner will get most of the starts at third for the Mets. He has had a decent year thus far, posting a .318/.362/.455 line with a homer and 10 RBI in 44 at-bats. Again, he's only an option in very deep leagues and only in the short-term. If you fit that bill, Turner is worth the add.

Talk with me 140 characters at a time on Twitter, @MBeller.

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