By Brian Robb, CBS Boston

BOSTON — The Celtics may be the No. 2 seed in the Eastern Conference at the moment, but they’ve also been a flawed squad since the All-Star break. Despite ranking as a top-10 offense over the course of the regular season, they’ve slumped to 23rd in the league over the past month in that department, as their secondary scoring options have started to cool off.

After a quiet trade deadline, Danny Ainge knows that the offense is an area that could still use an upgrade and that’s likely why the Celtics were reportedly after free agent forward Omri Casspi this weekend. Marc Stein of ESPN.com reported Boston’s interest on Sunday in the former Pelicans wing who was waived last month after suffering a broken thumb. The 6-foot-9 swingman has healed up ahead of schedule in the meantime, making him an appealing target for teams in need of the bench boost. The Memphis Grizzlies and Los Angeles Clippers also reportedly had interest in Casspi.

The pitches from Boston, Memphis and L.A. to come join a playoff team down the stretch was apparently not enough to entice the 28-year-old however, as Stein reported that Casspi is set to sign with the Minnesota Timberwolves on Monday. The forward got a strong pitch from Wolves team president and head coach Tom Thibodeau over the weekend in New Orleans, which was enough to seal the deal, according to Stein.

The development comes as another blow to a disappointing buyout market for the Celtics, who also missed out on other potential targets in the past few weeks. Casspi particularly ended up being the best potential free agent fit on the market for Boston given his elite 3-point shooting (39.4 percent from the field on the season).

The journeyman veteran has played for four different teams already in his eight NBA seasons but he has yet to qualify for the postseason in any year over that span. That could have changed for Casspi in Boston but the allure of playing regular minutes for Minnesota in place of the injured forward Nemanja Bjelica was more enticing. With guaranteed playing time up north, Casspi will have a chance to build better value for himself on the free-agent market this summer, something that wouldn’t have been a sure thing in Boston in a crowded frontcourt.

The miss on Casspi is unfortunate for Brad Stevens though given the fact that the versatile forward could have been a remedy for those issues. Boston has not received reliable production from their stretch bigs in recent weeks, as Jonas Jerebko and Kelly Olynyk have combined to shoot 1-of-10 from downtown in their last five games. In order for the Celtics to effectively space the floor well around Isaiah Thomas, they need knockdown shooters, and that’s been area on the decline team-wide as well (32 percent in last 10 games).

Casspi is a proven commodity from beyond the arc, having knocked down 39 percent or more of his 3-point attempts for the past three seasons. His height (6-foot-9) would have made him an appealing option for Stevens to go small with in lineups with Jae Crowder handling the 4. Instead, Stevens will be left making the best of a flawed roster, hoping his shooters snap out of a funk before the postseason arrives.

Brian Robb covers the Celtics for CBS Boston and contributes to NBA.com, among other media outlets. You can follow him on Twitter @CelticsHub.