How concerned should Dodgers be with performance of Joel Peralta?

So there was a certain amount of displeasure voiced Tuesday after Dodgers Manager Don Mattingly elected to bring in reliever Joel Peralta with the bases loaded and one out in the seventh inning of a 1-1 game.

Certainly, Peralta’s immediately giving up a grand slam did not help Mattingly’s cause, but of greater concern should be the performance of Peralta overall.

He started the season looking like a great addition, a veteran to help settle in several young bullpen arms. And then there was his own performance- – he did not allow a run in his first seven appearances, and with Kenley Jensen out, picked up three saves.

It looked as if Andrew Friedman wisely had brought along the right reliever from Tampa Bay to help stabilize an unsettled bullpen.

Only then the 39-year-old went on the disabled list with a sore shoulder. He missed two entire months with the nerve injury that at one point doctors thought could only be improved by surgery to remove a disk from his back.

Since his return, he has been wholly unreliable, a completely different pitcher.

In the 15 games he’s appeared in since his return, Peralta has a 6.17 earned-run average and a 1.80 WHIP -- this from a guy who did not allow a single run in his first seven games before the injury.

After that great initial start, the Dodgers’ bullpen is again a sore spot. It posted a 2.82 ERA in May, then a 6.27 ERA last month (corrected). Now it has two new pieces in right-hander Jim Johnson and left-hander Luis Avilan, both acquired at the trade deadline from Atlanta.

So in August, the bullpen -– the team’s great 2014 playoff failing -– remains a work in progress.

But what to do with Peralta? Right now, there’s no way he should be used with a game on the line. Maybe he just needs more time, and maybe he is still headed for surgery. For now, it’s best to simply use him when games are nearly out of hand, and not in clutch, late-game moments.