The A's had the lead entering the bottom of the seventh inning Saturday night in Pittsburgh, but their bullpen couldn't hold the lead. J.B. Wendelken was hit hard, giving up three runs in an inning as the Pirates rallied for a 6-4 win.
However, there might be a much more pressing issue for the A's than a loss to the Pirates.
All-Star closer Blake Treinen was unable to pitch Saturday after he woke up with elbow soreness. He will not pitch Sunday, and then will be re-evaluated Monday, according to A's manager Bob Melvin.
Treinen isn't sure how serious the elbow issue is, though.
"It kind of hit me [Saturday] morning, and I'll get through the off-day and pick it back up from there," Treinen told The San Francisco Chronicle's Susan Slusser. "It's just kind of fluke soreness. It just popped up. I'm not a doctor, so I don't know a ton about it."
With Treinen unavailable, Melvin had slotted Lou Trivino into the closer's role, leaving Wendelken with the seventh. That clearly can't be the plan going forward if Treinen is unavailable.
Treinen never has been on the injured list during his four big league seasons, but if he is forced to miss extended time, it would be a big issue for the A's.
One year after having one of the best bullpens in Major League Baseball, the A's relievers have struggled early this season.
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If Treinen is forced to miss a significant amount of time, Oakland will need Wendelken, Joakim Soria and Fernando Rodney to turn the corner and fast. Rodney (6.23 ERA), Soria (6.28 ERA) and Wendelken (5.85 ERA) have struggled mightily to begin the season and shown little signs of coming out of their prolonged funk.
A trip to the injured list for Treinen would put a lot of pressure on guys who have underperformed to this point and could send the A's season into a tailspin.