Jeff Clark: It could be Kelly again, but I'll go with Terry Rozier. He's athletic and quick enough to be a problem for the Cavs guards to keep track of. Same goes for Jaylen Brown really. They both are low on experience but high on talent and explosiveness. Also, Marcus Smart is a walking X-factor. Basically I'm saying it could be anybody (and that speaks to the depth of this team).
Keith Smith: Avery Bradley. He needs to play like he did for most of the Washington series for Boston to have a chance. Like they did two years ago, the Cavaliers will focus on making someone but Isaiah Thomas beat them. Bradley has to be there as a guy who can consistently knock down shots. And he's probably drawing Kyrie Irving on the other end. He'll have to contain Irving for the Celtics to get enough stops to stay in games.
Lachlan Marr: I think it’s going to be Avery. He’s been a big factor in the few wins the Celtics have managed to score against the Cavs, and if Boston wants to get some wins in this series then Bradley is going to need to play at his highest level. I also think Jae could be decisive in this series, no one is expecting him to outscore or outplay LeBron, but if Crowder can keep LeBron from completely taking over then Jae will prove his worth.
Sean Penney: I'll go with Jaylen Brown. He can give the Cs some quality minutes off the bench guarding LeBron if he can manage to stay out of foul trouble. In his limited playing time in the postseason, Brown has shown little sign of any rookie jitters. Did you see that play he made against Washington in Game 7 off the lob from Smart? This kid can make some flashy plays and isn't shying away from the moment. Boston's bench has an advantage over Cleveland's, so guys like Brown will be needed to step up.
Alex Kungu: The obvious choice here seems to be between Jaylen Brown or Jonas Jerebko. If Brown can come in the game and give the Celtics some quality defense against Love, James, and Irving and allow Horford to focus on keeping Thompson out of the paint, it could go a long way in helping the Celtics contain the rest of the Cavaliers.
Bill Sy: Swedish Larry Bird. Jonas Jerebko hasn’t played since Game 4 in D.C., but like Gerald Green against Chicago, Jerebko’s number could be called based on the matchup. The 6’10 Swede could serve as the fourth big in a front line defense that will have to contend with Kevin Love, Tristan Thompson, and LeBron James, and Channing Frye.
Jared Weiss: Smart needs to do what Smart does. The junkyard dog that tore through Game 7 needs to feast every night if the Celtics have a chance. He’s going to guard a lot of LeBron and will be the key to the Celtics surviving the battle on the boards, as the Cavs bigs will box the Celtics out of the arena. Hitting shots would be nice, but this is his defensive calling.