Tim Sherwood has revealed he "snapped" his hamstring by kicking a water bottle carrier in frustration during Aston Villa's 2-2 draw with Sunderland on Saturday.
The Villa boss lashed out when Carles Gil was denied a late penalty and booked for diving.
"I've done my hamstring," Sherwood told the club's official website. "I never did it as a player. I have now done it as a manager.
"I was going to kick the bottles forward but there were too many people so I thought I'd be polite and backheel them and snapped my hamstring.
"It feels bad.
"I must have looked like a spoiled brat. I tell my kids not to behave like that.
"Before today, I thought I had calmed down."
Sherwood becomes the second Premier League this manager this season to sustain an injury more usually associated with players - Ronald Koeman underwent surgery on an Achilles injury and missed Southampton's opener against Newcastle United.
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