However, Skrtel has forced his way back into the starting lineup at Anfield, and his boss is keen to highlight his good form.
"When you get your opportunity, you need to grab the shirt and he has come in and done that," Rodgers told the Liverpool Echo. "I thought he was brilliant [against Manchester United]. I called him into my office the other morning just to recognise his performance at Old Trafford.
"Martin defended crosses into the box, he was clever in his defending and very assured and composed on the ball.
"It's great credit to his professionalism that when he wasn't in the team he continued to work and was fighting every day to show he could play in the team."
The Reds travel to the Stadium of Light to face rock-bottom Sunderland today.