Limited roles for relievers Guerrier, Strop

OAKLAND, Calif. -- Relievers Matt Guerrier and Pedro Strop joined the Chicago Cubs on Wednesday, with both expected to bolster a struggling bullpen after they were acquired Tuesday in separate trades.

However, Cubs manager Dale Sveum said he doesn’t plan to slip either into the eighth-inning setup role in front of closer Kevin Gregg.

“I think [Blake] Parker pretty much put himself in that role right now,” Sveum said. “It’s pretty much going to be Parker and Gregg in those last two innings.”

But roles could shift quickly, as Gregg is seen as a prime trade candidate, along with tonight’s starting pitcher against the Oakland Athletics, Matt Garza.

Chicago could use some stabilizing outings from Guerrier and Strop, that’s for sure. The Cubs’ bullpen ERA of 4.32 is tied for 12th out of 15 National League teams, and they’ve converted just 18-of-35 save opportunities.

To make room for Strop and Guerrier, reliever Shawn Camp was designated for assignment and left-hander Chris Rusin, who made a spot start Tuesday, was optioned to Triple-A Iowa.

Strop, 28, acquired from the Baltimore Orioles along with Jake Arrieta for Scott Feldman, is an intriguing player, having pitched so effectively as a late-inning reliever for Baltimore last season, posting a 2.44 ERA in 70 games. His ERA has swelled to 7.25 this season. The right-hander has walked 15 in just 22⅓ innings, and he became a target for Camden Yards boo birds.

Strop said he tried changing his mechanics too quickly when things started going south, which got him out of rhythm. But he’s ready to begin anew.

“I come here with a clear mind,” he said. “I’m going to forget whatever happened and start over. I’m a Cub, not an Oriole anymore. I’ve turned the page.”

Guerrier, 34, is hoping a change of scenery can change his fortunes, too, after he was acquired from the Dodgers for fellow reliever Carlos Marmol. Guerrier was designated for assignment Sunday after posting a 4.80 ERA in 34 games. He last pitched Friday, and both he and Strop are available tonight.

“Obviously things weren’t going exactly as I’d liked them in L.A.,” Guerrier said.

Team notes

With Rusin being sent down, the Cubs haven’t announced a starter for Sunday, which would have been Feldman’s turn before he was traded Tuesday to Baltimore.

Sveum confirmed that Sunday’s starter would be a minor league call-up. One option is Guillermo Moscoso, who threw 6⅓ innings Tuesday for Iowa and got the win over Memphis. Moscoso has seen big league time with the Texas Rangers, Colorado Rockies and Oakland. He would be on his regular four days’ rest were he to go Sunday. But it’s worth noting he has a 4.63 ERA in Triple-A and walked four Tuesday.

The Cubs also figure to give a starting shot at some point to Arrieta, who was acquired from Baltimore along with Strop and was assigned to Iowa.