TV Guide reports that Trucco will appear in an episode of the show in April.
He is expected to play Robin's old "crush".
Rumours have suggested that Trucco could return in several episodes next season and be an important character in Robin's life. However, it is not clear how that would affect his current show Fairly Legal.
Trucco has also starred in One Tree Hill and Battlestar Galactica and recently appeared in several episodes of Castle.
How I Met Your Mother airs on Mondays at 8/7c on CBS.
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