Bowe scored six GUINNESS PRO12 tries in 12 appearances for Ulster last season, and will undergo surgery on Monday.
And Doak, whose Ulster side recorded a 24-17 bonus-point victory over Cardiff Blues on Friday evening to stay fifth in the GUINNESS PRO12, concedes the news is a blow for his side.
"When the surgeon has a look we should have a better picture of how long he is likely to be out for," he said.
"But we don't think it will be weeks and weeks.
"It's unfortunate for Tommy but we wish him a speedy recovery and want him back out on the pitch as quickly as possible."
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