J.J. Watt knew immediately when he’d get a chance to face his younger brother, T.J.

When the former Wisconsin linebacker was drafted in the first round by the Pittsburgh Steelers, the eldest Watt offered up this thought:

The former Wisconsin stars will be the talk of the Christmas matchup, but they technically won’t square off on the field.

Well, unless J.J. can convince Bill O’Brien to make an exception.

According to T.J.’s new defensive coordinator, Keith Butler, J.J. already put in a special request to line up on offense against the Steelers.

“(J.J.) is hoping he can play fullback once or twice when we play them this year so he can try to run over his brother,” Butler said in an interview with Steelers.com.

J.J. has lined up on offense several times in the NFL. The former Central Michigan tight end has three career catches, all of which were for touchdowns.

That would certainly be must-see TV on Monday Night Football.

If he does, perhaps J.J. should take some tips from his other younger brother Derek, who is a fullback for the Los Angeles Chargers. J.J. hasn’t had a chance to line up against him yet, nor will he during the 2017 regular season.

The best chance for everyone to get some Watt-on-Watt combat could very well be on Christmas.