Joel Hanrahan's season is over, as "the flexor tendon in his right forearm has torn off the bone." He'll need surgery, and he might need Tommy John surgery as well. If it's just the flexor tendon, he should miss six to nine months, which could put him on track to be ready for next year's spring training.
This is bad news for Hanrahan, who was set to become a free agent next offseason. (I was going to say "terrible news," but then I remembered that Hanrahan is a very rich man. The ".04 million" in Hanrahan's $7.04 million salary isn't far from what I make in a year.)
In the article linked above, Brian MacPherson links Hanrahan to previous Red Sox pitchers like Eric Gagne and Bobby Jenks, suggesting that high-profile relievers are a very risky investment.