Beckett was in good spirits on Tuesday during a radio appearance, though he has not pitched since leaving his last outing on July 31 in the third inning due to a back spasm.
"I had a lot of anxiety and stress things going on, exterior distractions. I don't think a lot of it was great for my back," Beckett told WAAF. "Then going out and pitching on that mound, it was very wet and my back just locked up on me."
One of those distractions was trade rumors and, coincidentally, Beckett's last outing fell on the non-waiver Trade Deadline.
"That week was so much different for me because they were all rumors," the right-hander said. "They were apparently not being brought up by the Red Sox, because I was hearing from everybody that none of this was true and everything like that, but I still had to answer questions about it, so it was very confusing. That's where I think the anxiety comes in. It's not so much stress, it's more anxiety than anything because you're not real sure how things are going."
Beckett also dismissed the notion that the Red Sox (55-55) have a dysfunctional clubhouse.
"No, it's the exact opposite," he said.
As for his upcoming start, manager Bobby Valentine does not expect Beckett to be hampered by any lingering effects from his back spasm or stiffness.
"He'll only be limited if his back hurts again, his arm is fine," the manager said before Tuesday's game against Texas. "I don't think he'll be limited."
Beckett is 5-9 with a 4.54 ERA in 18 starts this season. The Red Sox are 7-11 when he takes the mound.