DIMINUTIVE defender Caleb Daniel's season is in doubt, with the Western Bulldogs star re-injuring his left hamstring in Sunday's loss to Brisbane.

Daniel played out the game but immediately pulled up sore, with subsequent scans revealing he had reaggravated the injury.

The Bulldog initially injured his hamstring in the final quarter of the round 15 match against Port Adelaide, and missed the following two games.

Daniel's move down back has been surprisingly successful. Picture: AFL Photos

Western Bulldogs' medical services manager Chris Bell said the club would take no risks with Daniel, who has had a breakout year playing across half-back.

"This is the second time he's damaged his hamstring this year, so we're going to take our time in returning him to play," Bell said.

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"We're still to set out his exact timeframe and will confirm this over the coming weeks."

Daniel has been averaging a career-high 26.5 disposals per game in 2019 and his clean ball use and drive from half-back has been instrumental in some of the Dogs' best wins this season.