WWE announced Wednesday that Rowan of The Bludgeon Brothers will undergo surgery this week to repair a torn right bicep.
Rowan and Harper dropped the SmackDown Tag Team Championships to New Day in a No Disqualification match on Tuesday's episode of SmackDown Live.
At SummerSlam on Sunday, The Bludgeon Brothers lost to New Day by DQ after attacking them with their mallets.
PWInsider's Mike Johnson reported Rowan suffered the arm injury during the SummerSlam bout.
The Bludgeon Brothers beat The Usos and New Day in a Triple Threat match for the SmackDown Tag Team titles at WrestleMania 34 in April.
They went on to hold them for 135 days before dropping them to New Day, which was the second-longest reign in the history of the titles.
Rowan signed a developmental deal with WWE in 2011, and he has been on the main roster since getting called up as part of the Wyatt Family in 2012.
This marks the second major injury the 36-year-old has suffered in less than two years, as he missed eight months across 2016 and 2017 with a torn rotator cuff.
WWE has yet to announce an expected timetable for Rowan's return from his latest injury.
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