Lupul aggravated a knee injury in Tuesday's loss to the Rangers and is expected to be out for about a week, Paul Hendrick of Leafs TV reports.It's just the latest item during Lupul's injury-plagued career, as he's been unable to suit up for more than 70 games in each of the last five non-lockout years. His latest setback is related to the knee injury he suffered Dec. 31 against the Bruins, which sidelined him for nearly the month. The Leafs are hopeful he can avoid an absence of that length this time around, but given Lupul's history, that can't be considered a given. With Lupul set to miss time, David Clarkson should reclaim a lineup spot after serving as a healthy scratch for the Leafs' last two contests.