I would have sent Valdez back out for the 9th and sent in Ottavino only if needed. Even though the Sox won, it was costly in bullpen usage. If Valdez gets thru the 9th, Ottavino and Robles get some rest.
The Sox have a somewhat depleted bullpen, but it is anchored by 3 pretty good long relievers: Whitlock, Richards, and Valdez.
The Sox lineup was also hit, but Arauz, of whom I have never been a fan, has come through with hits and--surprise, surprise--highly competent bunts. Yesterday the Sox had three successful bunts in a game for the first time--according to WEEI--since 1993. Sabermetrics can stuff it.