The Nottingham fighter controversially halted his opponent in the ninth round in November last year, and ahead of their highly-anticipated rematch, Khan says that he can't pick a winner.
The former WBA and IBF light welterweight champion told Sky Sports News: "You know it's hard, because at first I went with Froch, I was saying he was going to win the fight with his pressure and he knows what to expect.
"Then when I saw the highlights of the [first] fight, I thought Groves did give him a boxing lesson for the first eight rounds, so I think it's hard to say who is going to win this fight.
"Boxing-wise, Groves is a better fighter, but I think his fitness might let him down. Froch comes on in the later rounds, and is stronger, so it's just whoever is strong at the end of the fight will win."
Khan beat Luis Collazo in his last fight earlier this month.