Danny Ainge

Boston Celtics general manager Danny Ainge takes questions from reporters during NBA basketball media day at the team's training facility Monday, Sept. 26, 2016, in Waltham, Mass.

(AP Photo/Steven Senne)

The Boston Celtics have held "preliminary" trade discussions about several big men, according to the Vertical's Shams Charania.

Charania did not expand on his report, so it's not clear which players the Celtics have looked into. Don't be surprised if they would like a big, physical guy to contest shots and box out. Despite a recent surge in rebounding, they still rank dead last on the defensive glass. Their defense has improved substantially over a seven-game winning streak, too, but still ranks 19th in the NBA.

When pondering who might interest the Celtics -- Andrew Bogut? Jusuf Nurkic? Serge Ibaka? Somebody else? -- keep in mind they have prioritized flexibility and maximum cap space for this summer. They won't take on future money that would hurt their chances of chasing, say, Gordon Hayward or somebody like that. A short-term rental could work, but the front office would also need to weigh whether the cost makes sense if they don't have a real chance to win a title this season (and hey, who knows, maybe they now consider the Cleveland Cavaliers vulnerable). The Celtics could also take a look at the waiver wire or make room for somebody like free agent Larry Sanders, who they worked out last month.

As much as the Celtics need more size, it's worth considering that all their frontcourt shooting has opened lanes for Isaiah Thomas, helped Marcus Smart excel as a post-up point guard, and damaged opponents whose big men can't guard the perimeter. Adding a bruising and/or athletic center could help, but there would be a tradeoff in most cases.