Kessler injured his right hand in the first half of the Trojans' 17-14 victory Saturday at the Coliseum.
After completing only 13 of 27 passes for 164 yards and a touchdown, Kessler said he had struck his hand several times on opponents' helmets and pads. He emerged from the locker room with ice taped to the back of his hand and said X-rays were negative.
USC receivers dropped four passes, but Kessler also struggled after the initial hit to his hand.
"I think you did see a difference in the game in his accuracy and ability to grip the ball," Kiffin said during a teleconference with reporters. "That shows up in the passing game."
Lee, who caught six passes for 72 yards, said he suffered an ankle injury on a punt return. He sat out for subsequent returns but continued to play and said afterward that the injury was not serious.
"Coach Kiffin wouldn't allow me to be out there if it was really something serious," he said.
Kiffin said he was pleased with the performance of the defense and special teams in a victory that improved the Trojans' record to 3-1.
But the offense "left yards and points out there," Kiffin said.
Kiffin had complimented the offensive line after USC's 35-7 victory over Boston College. He said Sunday that the line was "not playing great" and had "too many mistakes."
Kessler was sacked three times, including one that resulted in a fumble, against Utah State.
Kiffin said left tackle Chad Wheeler, a redshirt freshman "had a war last night on his hands" and that although he gave up the sack that led to the fumble, he "held his own" and also had "some great plays."
The line will be challenged when the Trojans face Arizona State defensive tackle Will Sutton, the reigning Pac-12 defensive player of the year, who had 20 tackles for losses last season.
Arizona State is coming off a 42-28 loss at Stanford.
The Sun Devils opened the season with a 55-0 victory over Sacramento State and then defeated Wisconsin, 32-30, in a game that had a controversial finish.
Kiffin said it was advantageous for the Trojans to have played against Utah State and quarterback Chuckie Keeton before playing Arizona State.
"It was good to have a no-huddle, hurry-up offense to line up against," he said.
USC linebacker Morgan Breslin sat out the opener against Hawaii because of injury, but he has made his presence felt since returning.
Breslin, a senior, had four tackles, including three for losses, against Utah State. Breslin had two of the Trojans' four sacks and the team had 10 tackles for losses.
Breslin ranks seventh nationally with 1.3 sacks per game. He is eighth in tackles for losses, averaging 1.8 per game.
USC is ranked first nationally in red-zone defense, second in tackles for losses, third in rushing defense, fourth in total defense and sacks, 10th in interceptions and 11th in scoring defense.
USC's game Saturday at Arizona State will kick off at 7:30 p.m. and be televised by