Red Sox option Kyle Kendrick, recall lefty reliever Robbie Ross

The Boston Red Sox have optioned struggling starter Kyle Kendrick to Triple-A Pawtucket and replaced him on the roster with lefty reliever Robbie Ross.

Remember back in spring training when Kyle Kendrick was making a strong case for earning a spot in the Boston Red Sox rotation? It didn’t take long for the team to realize they weren’t going to get that type of performance out of him once the games began to count.

The Red Sox optioned Kendrick to Triple-A Pawtucket after the left-hander took the loss and surrendered six earned runs for the second time in as many starts.

Kendrick has lasted a total of only 8 1/3 innings over which he’s allowed 12 earned runs for a brutal 12.96 ERA since taking the rotation spot from the injured Steven Wright. Boston’s bats have started to wake up recently, but even last year’s powerhouse lineup would struggle to rally from the deep holes Kendrick has been putting them in.

“This game’s about results,” Kendrick told the Boston Herald. “I mean, you’ve got to go out there and give the team a chance to win. The last two starts haven’t been that.”

It’s unclear who will take Kendrick’s place, although an off day on Monday allows the Red Sox to skip his next turn in the rotation to give them some extra time to line up a replacement.

In the meantime, Boston will bolster its bullpen by adding left-handed reliever Robbie Ross, Jr. With Kendrick and Tuesday’s starter Drew Pomeranz both failing to make it through the fifth inning, the bullpen could use some reinforcements.

Ross started the season with the big league team, only to be demoted when the Red Sox decided they didn’t need three lefties in the bullpen. Robby Scott surpassed him as the top option to face left-handed hitters and the team still has a baffling attachment to Fernando Abad, which left Ross as the odd man out.

While Ross was understandably disappointed by his demotion, he’s done everything he can since to earn a trip back to Boston. The lefty has allowed only one run over six innings in which he’s struck out seven batters.

The Red Sox are back to having three lefty relievers, which may only last as long as it takes for the team to decide who replaces Kendrick in the rotation. That gives Ross a short window to prove he belongs in the big leagues.

As for who will take over the No. 5 spot in the rotation, Boston will have a few options to choose from. Brian Johnson and Henry Owens would be the obvious choices, since both have performed well in Pawtucket and are already on the 40-man roster. Hector Velazquez has been even better this season, owning a 1.23 ERA through four starts, although calling him up would require making a 40-man roster move.

Perhaps if Ross proves himself worthy of retaining a spot in the bullpen then designating Abad for assignment could clear a path for Velazquez. That would certainly make some sense, although it’s doubtful that the Red Sox would cut bait with Abad in order to add a short-term solution to the roster.

With David Price scheduled for a rehab start this weekend, a return to the Red Sox rotation could come before the end of the month. Whoever takes Kendrick’s spot may only be needed for a couple of starts, which could dictate which pitcher the team turns to.

Next: Red Sox prospect watch

One thing we can count on is that it won’t be Kendrick. With Price’s return on the horizon and a number of younger options with more upside performing well in Pawtucket, we may have seen the last of the 32-year old right-hander in Boston.