Clifton was originally a fifth-round draft pick by the Coyotes in 2013, but after not signing with Arizona, he ended up joining AHL Providence in August of 2017. The Quinnipiac product's efforts there resulted in him inking a deal with the big club, and then injuries led to the 24-year-old earning an NHL promotion this past season. Over 19 regular-season contests with Boston, Clifton logged just one helper, but in the process, he played well enough to establish himself as a valuable member of the team's blue-line rotation. During the Bruins' postseason run, Clifton chipped in two goals and five points in 18 games and earned himself an extension, a move that gives him some financial security, while giving the team a solid blue-line piece at a team-friendly cap cost. Looking ahead, Clifton isn't a big fantasy factor, given that he doesn't see much power-play duty, but he is capable in the transition game and isn't rattled by the physical aspect of NHL duty, despite his 5-foot-11, 175-pound frame.