Bullpen might be key to Angels’ success

Reporting from Tempe, Ariz. — For much of the Angels’ success from 2002 to 2009, when they reached the playoffs six times and won a World Series, their bullpen offered the security of a maximum-security prison on lockdown.

Whether it was Francisco Rodriguez to Brendan Donnelly to Troy Percival, or Donnelly to Scot Shields to Rodriguez, or Darren Oliver to Shields to Rodriguez, Manager Mike Scioscia’s key relievers routinely held late-inning leads.

But sometime in 2010 — or maybe it was the end of 2009, when closer Brian Fuentes threw an ill-fated up-and-away fastball that Alex Rodriguez drove for a pivotal 11th-inning home run in Game 2 of the American League Championship Series at Yankee Stadium — the back of the Angels’ bullpen, so sturdy for so long, began to buckle.

Shields, the durable and dependable right-hander who was named Sports Illustrated’s setup man of the decade, finally broke down, injuries and ineffectiveness leading to retirement after 2010.

Fuentes, who led the AL with 48 saves in 2009, slipped so much in 2010 he was traded to Minnesota in August for a mid-level prospect. The bullpen went 18-19 with a 4.03 earned-run average and a league-leading 233 walks that season.

Fernando Rodney was so shaky in 2011 he lost his closer job after his second outing and was replaced by rookie Jordan Walden, who showed promise with a 2.98 ERA and 32 saves but led the AL with 10 blown saves.

Left-hander Scott Downs (6-3, 1.34 ERA in 60 games) was sharp in a setup role, but the Angels went through several struggling seventh-inning men (Rodney, Kevin Jepsen, Michael Kohn) before sinkerball specialist Bobby Cassevah stabilized the spot in August.

Jepsen seized the setup role late in 2009 but was undermined by a knee injury and control problems that were so bad that last May, during an intentional walk to Paul Konerko, he threw a pitch six feet over the head of catcher Hank Conger, allowing the Chicago White Sox to score the tiebreaking run.

Rodney was so good in 2010 (4-3, 4.24 ERA, 14 saves) that fans clamored for him to replace Fuentes as closer. He was so bad last season that Scioscia banished him to a mop-up role as the Angels slipped from playoff contention in September.

“The bullpen is a very unpredictable and unusual place,” said Angels General Manager Jerry Dipoto, a former big league pitcher who handled several relief roles. “It’s a very topsy-turvy world at times.”

The Angels can’t afford volatility this season. Their rotation and lineup are built to play deep into October, but their bullpen is the one area they seem vulnerable.

After passing on free-agent closers such as Heath Bell, Ryan Madson and Francisco Cordero this winter, Dipoto will entrust the ninth inning to Walden, whose 99-mph fastball earned him a trip to the All-Star game last summer but whose late-season meltdowns might have cost the Angels a wild-card spot.

By adding a pair of 39-year-old right-handers — LaTroy Hawkins and Jason Isringhausen — to a short-relief corps headed by the 36-year-old Downs, Dipoto will bank on a trio he admits is “a little long in the tooth” to bail out the Angels from seventh- and eighth-inning jams.

The upside: Hawkins regained velocity on his fastball after shoulder surgery and went 3-1 with a 2.42 ERA for Milwaukee last season. Isringhausen, who has 300 saves, held right-handers to a .178 average with the New York Mets in 2011. And Downs has been consistent the last five seasons, with a 2.17 ERA in 322 appearances.

“We have guys with track records, history,” Dipoto said. “Izzy throttled right-handed hitters a year ago. … LaTroy has 15 years of big league experience, and he has a lot of confidence with absolutely no ego.

“Same thing with Downs. He’s been as good as anyone in baseball the last couple of years. … And we have a guy on the back end who is throwing 100 mph and coming off a pretty good cameo in the big leagues.”

The Angels expect their rotation to ease the burden on the bullpen by pitching deep into games. Dan Haren has thrown 200 innings or more for seven consecutive seasons, Jered Weaver passed that mark the last three years, and C.J. Wilson and Ervin Santana did it the last two seasons.

“If the starters go deep in games, the bullpen will get proper rest,” pitching coach Mike Butcher said. “There will be times they’re out there more than you want them to be — you always go through those phases — but I think they’ll be well-rested, and I know they’ll be prepared.”

Walden should benefit from the growing pains he endured last season. He came to camp determined to improve a changeup he rarely threw last season and unfazed by winter speculation the Angels would sign or trade for a proven closer.

“He learned a lot last year,” Butcher said. “I think he’s a lot more confident. He understands what he needs to do to get himself ready for games, how you turn the page, how you make adjustments. He’s in great shape. I’m really excited about what he’s going to bring.”

mike.digiovanna@latimes.com

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