Pavel Kubina, Simon Gagne ruled out

WASHINGTON -- The Tampa Bay Lightning will be without the services of veterans Pavel Kubina and Simon Gagne in Sunday's Game 2 against the Washington Capitals.

Both players suffered head injuries in Game 1, a 4-2 win for the Lightning.

Veteran defenseman Randy Jones will replace Kubina, while minor league forward Blair Jones will make his NHL playoff debut up front.

Jones has been physically able to play for a few days, but Tampa Bay coach Guy Boucher said he was reluctant to tinker with his lineup during the latter stages of the Pittsburgh series because the team was doing well.

Gagne and Kubina are considered day to day.

"There's a possibility for maybe one of them Tuesday, maybe both. But it's day to day," Boucher said.

As for the Capitals, defenseman John Carlson and veteran forward Mike Knuble both returned to the lineup.

Carlson missed the third period of Game 1 with what appeared to be a back issue, but skated Sunday morning.

Knuble, who has missed the past three games with an apparent hand injury, returned after Capitals coach Bruce Boudreau said earlier in the day that he doubted the forward would be available for Game 2.

Scott Burnside covers the NHL for ESPN.com.