Bullard, the Premier League's player of the month for November, left the pitch in tears after landing awkwardly following a challenge in the 3-0 loss.
The injury came in just his fifth appearance since returning from an eight-month lay off following surgery on his other knee.
Tumble:Jimmy Bullard was injured after this fall while challenging AstonVilla's James Milner and had to be helped off the pitch by medicalstaff (below)
Bullard and Hull feared the worst but, after a scan this evening, manager Phil Brown was relieved the injury was not as serious as first thought.
'I am sitting here like a man waiting in the emergency room for his wife to give birth,' Brown told Sky Sports News. 'It's been an horrendous day for me but I'm now very hopeful Jimmy will be back on the field of play before the transfer window closes.
'That's what I and Jimmy will be looking at. Hopefully we'll have him for three to four months of the season still.'
Bullard marked his full Hull debut with a starring role in the 2-1 win over Stoke. The £5million signing from Fulham then scored in draws with West Ham and Manchester City, the latter being met with a choreographed celebration mimicking Brown's famous half-time team talk on the pitch at Eastlands last season.
'He's a tremendous character, the way he is he just wants the ball and to please people,' Brown added. 'He's that kind of character, there are not so many about.'
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