It's been a little over a month since the All-Star Break. Who has set the standard for second-half superiority? Let's take a look.

At the head of the class are Jose Valverde and John Axford. The two are tied for the second-half saves lead with 11 each. Valverde (2.75 ERA, 35 saves, 8.43 K/9) was considered a mid-tier option before the season, but the Tigers' reliever is having a career year. With the Tigers leading the AL Central, Valverde could surpass the career-high 47 games he saved in 2007.

Axford (2.40 ERA, 34 saves, 10.86) is also having a career year, having already surpassed his single-season save mark. The K-Rod trade certainly made things interesting for Axford owners, but the competition has brought the best out of the mustachioed Brewers' closer.

Craig Kimbrel, Sergio Santos, Javy Guerra and Joel Hanrahan are also earning high marks in the second half, having yielded zero earned runs combined since the break. Given their first-half performances, Kimbrel and Hanrahan should come as no surprise. Guerra (1.57 ERA, 10 saves, 7.22 K/9), however, came out of nowhere to seize the Dodgers' job and it's encouraging to see him hit the ground running in the second half. Opportunity -- he has had only two save chances in August -- is the only thing holding him back.

Likewise, Santos (2.72 ERA, 25 saves, 12.14 K/9) emerged from the shadows when the ninth inning became murky in Chicago. Santos was made to be a closer and if he can hold off Chris Sale -- who has already vultured two saves in August -- he's a good bet to top 35 saves this season.

The aforementioned are helping owners push for a title. But some relievers are already pushing owners away from a title.

Chris Perez is one of those relievers. His 2010 stat line (3.30 ERA, 25 saves, 5.77 K/9) looks decent, but the Indians' closer has a 6.10 ERA and a 1.45 WHIP since the break. He never had a closer's arsenal, and now that he's handing out more free passes, expect this downward trend to continue. One silver lining for Perez owners: there's no one breathing down his neck in the Cleveland bullpen.

Kevin Gregg (4.20 ERA, 17 saves, 7.80 K/9, 6.00 BB/9) is also one of those relievers. The Orioles' closer has a horrific 6.75 ERA and a 1.88 WHIP since the break, aided largely by a four-run, zero-out performance on Sunday evening. Gregg isn't good, but as they showed with the trade of Koji Uehara, the Orioles aren't removing him from the ninth inning anytime soon. And as long as he's tallying saves, he'll be in someone's lineup. Even with a 6.00-plus ERA.

How did the rest of the major league bullpens fare this week? Let's take a look around the league:

Craig Kimbrel Joel Hanrahan Jonathan Papelbon Mariano Rivera John Axford Heath Bell

By his standards, Rivera (2.40 ERA, 30 saves, 7.80 K/9) is struggling. There's been no shortage of articles breaking down Rivera's pains, but this is just a minor speed bump for the alltime great. He's pitching better than last year and his arm would literally have to fall off for the Yankees to remove him from the ninth inning.

Ryan Madson Brandon League J.J. Putz Carlos Marmol Brian Wilson Jose Valverde Drew Storen Francisco Cordero Leo Nunez Andrew Bailey

Wilson was briefly sidelined with back spasms over the weekend, but the Giants' closer pitched, albeit miserably, on Monday night. Wilson (2.72 ERA, 35 saves, 8.66 K/9) hasn't lived up to his preseason hype but The Beard needs to be active in all formats. ... League (2.79 ERA, 30 saves, 6.52 K/9) has allowed one earned run and four hits in his last 9.2 innings. He's quickly working his way up the rankings.

Joakim Soria Jordan Walden Neftali Feliz Javy Guerra Kyle Farnsworth Sergio Santos Fernando Salas Chris Perez

Feliz (3.33 ERA, 23 saves, 6.65 K/9) has strung together four straight scoreless outings. It's a step in the right direction, but the Rangers' closer still has a long way to go. ... Farnsworth (1.96 ERA, 21 saves, 7.24 K/9) was placed on waivers last week, meaning he could be traded to a contender later this month. It'd be a shame to see him slide into the eighth inning with how well he's pitched this year, but that's the likely scenario if he's dealt.

Joe Nathan Mark Melancon Kevin Gregg Rafael Betancourt Jon Rauch Bobby Parnell

Huston Street hit the DL over the weekend, and in his place, Rafael Betancourt (3.54 ERA, one save, 10.80 K/9) picked up the save. Betancourt is expected to receive the lion's share of saves while the brittle Street recovers. It's a shame Rockies manager Jim Tracy opted for the safe Betancourt over the intriguing Rex Brothers (4.21 ERA, 12.27 K/9), but age often wins out in the ninth inning. ... Jason Isringhausen (3.46 ERA, seven saves, 7.99 K/9) notched his 300th career save last night, and now that the milestone has passed, the Mets are likely to turn to Parnell (4.31 ERA, 11.12 K/9). The young Mets reliever has greatly outpitched his stat line and should be the closer in Flushing for the foreseeable future. Owned in only two percent of leagues, he's a must-add in all leagues.

Jonathan Broxton

Backups who will ensure you're banking saves even if your closer goes down:

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