Angels’ Jordan Walden steps in as surprise setup man

Reporting from Oakland — 

After the Aug. 28 trade that sent closer Brian Fuentes to the Minnesota Twins, Manager Mike Scioscia said he would use the relief triumvirate of Kevin Jepsen, Francisco Rodriguez and Jordan Walden to set up new closer Fernando Rodney.

The first two names made sense. Jepsen has been one of the Angels’ primary setup men since 2009, and Rodriguez, though a rookie, has emerged this season as a fairly reliable right-hander.

But Walden? The 22-year-old right-hander had been in the big leagues for all of six days at the time, and he was being tabbed as one of the team’s top short relievers?

“That was very surprising,” Walden acknowledged this week. “It still hasn’t even sunk in that I’m here.”

Walden’s 99-mph fastball has sunk in rather quickly.

Though he hasn’t stormed onto the big-league scene like the other Francisco Rodriguez did at age 20 with the Angels in September 2002, Walden has been impressive enough in four appearances to warrant strong consideration for a prominent relief role.

He has struck out at least two batters in three of the four innings he has pitched, including a scoreless seventh in Wednesday’s 4-2 win over the Seattle Mariners.

“At times, your talent might outplay a guy who has experience with limited or eroding talent,” Scioscia said. “The bottom line is who can do the role?

“You can see a guy who’s been in the big leagues for five days all of a sudden fill a role because of talent. Jordan has talent we feel is going to play at a high level.”

Walden, a 6-foot-5, 220-pound Texas native, began the season at double-A Arkansas and spent only three weeks at triple-A Salt Lake before being promoted. The key to his quick ascent was the command of his slider.

“I couldn’t throw it for strikes, but when I got to triple A I found it,” said Walden, who also throws a changeup. “I used the same grip I used in college, but I threw it differently. I stayed behind the ball, throwing it like a fastball and letting the grip do the work.”

The Angels obviously think highly of Walden, but Walden knows he can’t get too full of himself.

“I’ve still got a lot to work on, and it’s going to take awhile,” he said. “I’ve got to throw strikes, not walk people, trust my stuff and let it work for me.”

Turf war

The Angels probably won’t be able to take batting practice on the field before Friday night’s game against the Athletics because the grounds crew needs about 24 hours to return the Oakland Coliseum playing surface to a baseball field.

The Oakland Raiders played the Seattle Seahawks in an NFL exhibition game there Thursday night, and Angels outfielder Torii Hunter, who has played in Oakland the day after a football game, is expecting less-than-optimal conditions Friday.

“It’s terrible,” Hunter said. “It chews up the outfield. The ball bounces different ways, and sometimes it skids like you’re skimming rocks on water. It’s weird. It could be a weird day. Brace yourself.”

Bring the heat

After giving up three runs, two hits and two walks in the eighth inning of Tuesday night’s 3-1 loss to the Mariners, and relying too heavily on his cut fastball and curve, Jepsen took a different approach Wednesday.

The results were far different too. Jepsen, leaning heavily on his 96-mph fastball, struck out two of three batters in a scoreless eighth, and the Angels won.

“I had been pitching almost backward, so I wanted to come out and use my fastball, go after guys, get back to the type of pitcher I am,” Jepsen said. “Once I got ahead of guys, then I used my other pitches.”

mike.digiovanna@latimes.com