The 24-million pound, club-record signing has not been in the Villa squad for the whole month of November despite making 11 appearances in the opening 12 fixtures of the season.
"The team I pick will be the team that I pick," Lambert said in a press conference. "I know what happens in training, and we will see what happens. I think the team that I pick will be the team that will try and go and win us a game. It's the way I've always done it, and it's the way I will always be."
It has been suggested Bent is being omitted from the side to avoid triggering a 3 million pound bonus payment to former club Sunderland when he reaches 50 league appearances - a claim Lambert strongly refutes.
"Is there a clause? That's not true," Lambert said. "I'm not sure where that came from. It is absolute drivel. Have there been any enquiries for Bent? No. Has he asked to be put on the transfer list? No."
The 43-year-old Scot has been utilizing youngster Jordan Bowery, signed from Chesterfield in the summer, in Bent's place and was keen to point out his reasons for doing so.
"Jordan Bowery's potential is extremely high and he is an unknown quantity which sometimes can work in your favor," Lambert said. "I see every day what goes on. We've got 20-odd guys in the same boat together which I pick from."
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