NEW YORK (WFAN) — Joba Chamberlain released news so fresh on Thursday that even his manager was caught off-guard.

The Yankees reliever, who severely dislocated his ankle while playing on a trampoline with his son in late-March, announced via Twitter that he’s set to throw off a mound on Friday.

“Update for everyone! Bullpen tomorrow, 1 step closer!!” Chamberlain tweeted. “Thank u for all the support!!

Manager Joe Girardi had no idea Chamberlain was about to take the next step in his rehab at the team’s minor-league complex in Tampa. The 26-year-old had previously thrown off a half-height mound.

“That, I’m not aware of,” he said.

Chamberlain hasn’t pitched for the Yankees since Tommy John surgery ended his season in 2011.

“Can’t wait for my roll call! #honored,” he tweeted to Yankee Stadium bleacher creature “Bald” Vinny Milano.

When do you expect to see Joba back in the Bronx? Sound off below…

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