The Roman empire wasn't built in a day, and Roman Polak's knee will take some time to recover as well.

The Maple Leafs defenseman has been diagnosed with a strain in his left knee and will be out of the lineup for four weeks, head coach Randy Carlyle told reporters Monday.

Polak was averaging over 21 minutes of ice time prior to suffering the injury, with three goals and two assists in 21 games to his credit this season.