Leddy was brought in by the Blues, along with Luke Witkowski, from Detroit on Monday in a swap for Jake Walman, Oskar Sundqvist and a 2023 second-round pick.
Leddy has registered 16 points in 55 games this season, including five power-play assists, and should cruise to the 10th 20-point campaign of his career. While the blueliner is unlikely to unseat Torey Krug for a spot on the No. 1 power-play unit, he should be in line to quarterback the second group.