Rusney Castillo

Boston Red Sox's Rusney Castillo bats during a spring training exhibition baseball game against the Atlanta Braves in Kissimmee, Fla., Friday, March 27, 2015. (AP Photo/Carlos Osorio)

(Carlos Osorio)

BOSTON - The Red Sox sent a message to their pitching staff with the release of pitching coach Juan Nieves almost two weeks ago.

Whether or not the addition of new pitching coach Carl Willis has helped, Red Sox starters have posted a much more respectable 3.55 ERA in eight starts since he took over the staff on May 10.

Now it's time to jumpstart the offense.

Boston has scored just 11 runs in its last six games. In 16 games this month, the team is hitting just .208 with a .279 on-base percentage and .334 slugging.

The Red Sox returned home to Fenway Park on Tuesday after a 10-game road trip in which they went 5-5. There was no change to the lineup.

"If it centered around one or two spots in the order, you might say, let's look to slide (Shane Victorino) in the two-hole like we did in Seattle," manager John Farrell said. "Or move him up ahead of a couple of guys in that bottom or middle third. We're in a situation where, to me, I think it's just the short shakeup would jump start us all, that's kind of having a little bit of a crystal ball. We have the capability here.

"I'm not saying that there won't be changes, whether that's to the lineup or whether that's to our position player group. But coming off the road trip, I thought, 'OK, lets get through the off day still maintain some stability.' But always with an eye to what changes might help us."

The obvious and most readily available answer for an offensive boost would be Rusney Castillo.

Despite a handful of injuries this spring, Castillo is hitting .333 with a .400 on-base percentage and .528 slugging in 10 games for Triple-A Pawtucket. To this point, the Red Sox have kept him in Pawtucket in order to ensure he gets everyday at-bats and build consistency.

But there's an increasing need in Boston.

Shane Victorino is hitting .353 with a .428 on-base percentage and in five games since returning from a hamstring injury, but is not playing every day.

In five games since being recalled on May 10, Jackie Bradley Jr. does not have a hit.

Farrell noted on Tuesday that Castillo left the Pawtucket Red Sox for the birth of his child, but a callup may be pending upon his return to the team.

"His timing, his ability to impact the baseball is starting to show up a little bit more," Farrell said of Castillo. "He's returned home obviously for the birth of his child. That's going to be a couple of days. Whether or not we allow him to get a game under his belt at Pawtucket before possibly looking at a change here, those are all possibilities."

Dustin Pedroia leads Red Sox starters with a .276 average and .777 OPS. Hanley Ramirez's .816 OPS leads the team, but he's slipped since his shoulder injury.

The offense needs help and Castillo could be in Boston sooner than later.

"I guess in the short, he's doing what he can to impact a potential change," Farrell said.

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