Mary Lynn Rajskub to Play Mitchell's Ex on Modern Family

Before she crushed on Jack Bauer, Mary Lynn Rajskub had feelings for a closeted gay man.

The actress, best known for her long-running stint on 24, will guest star later this season on Modern Family. As first reported by TV Guide, she'll portray Mitchell's high school girlfriend.

Rajskub actually started out as a stand-up comic. She recently appeared on It's Always Sunny in Philadelphia and Royal Pains.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.