JOBE Watson may be struggling to overcome the mental burdens of Essendon's well-documented 2012 supplements regime, his father and Bombers great Tim Watson says.

The 30-year-old was restricted to just one kick and eight handballs in his 200-game milestone against St Kilda on Sunday. The 110-point defeat was the Bombers' biggest ever loss to the Saints.

Watson said the stress surrounding the club's supplements investigation could be the reason behind Jobe's recent form slump.

"What's happened in the last few years, and you put aside the WADA appeal, this has been ongoing for three years and it has worn a lot of people down," Watson told Channel Seven on Monday night.

"And I think he's [Jobe] one of those because, in some ways, he's been the face of the football club.

"He's certainly been a leader through that period of time as well which has meant that he's felt the responsibility of the group through that period of time."

When asked if Jobe was carrying an injury, Watson said: "I think he has got some sort of a physical problem at the moment, but I'm not going to make any excuses for him because he didn’t play well yesterday at all."

On Monday morning, the Bombers skipper remained coy when asked about his own fitness.

"Whenever you go out there you're 100 per cent," Jobe said.

After Sunday's loss, former Essendon spearhead Matthew Lloyd said the ongoing investigation into the club's supplements program was taking its toll on the 2012 Brownlow medallist.

"I believe Jobe Watson is struggling as a result – he probably doesn't feel it – (of) the whole WADA situation and his job for two years was to hold these group of players together," Lloyd told radio station 3AW.

"I feel like it's got to him."