Jeff Goodman of WEEI.com and FoxSports.com has learned from a source Rasheed Wallace will sign a two-year deal with the Celtics for the mid-level, which is worth approximately $5.7 or $5.8 million per season. Free agents can sign on July 8.

The Celtics made an aggressive bid for the four-time NBA All-Star when Paul Pierce, Ray Allen, Kevin Garnett, Doc Rivers, Danny Ainge, and Wyc Grousbeck flew to Michigan to meet with him last week. Wallace had reportedly garnered attention from several championship-contending teams, including the Orlando Magic and San Antonio Spurs.

Wallace, 34, was selected by the then-Washington Bullets with the fourth pick in the 1995 NBA Draft. Kevin Garnett was selected with the fifth pick. Wallace has a career average of 15.0 points and 6.9 rebounds in over 1,000 games. He currently ranks ninth among all active players in blocks (1375). (Click here to see an example of his recent handiwork against the Celtics.)

Part of Wallace’s appeal is his inside-outside game. Listed as a forward-center, the 6-foot-11 Wallace is also dangerous from long range. Last season he shot 35.4 percent from behind the arc and led the Pistons in three-point shots with 113, just six less than Paul Pierce.

Even more important to the Celtics, he has proven postseason experience. Wallace has advanced to the playoffs in every season since 1997 and averaged 14.6 points and 5.7 rebounds in the postseason. He won the NBA championship with the Detroit Pistons in 2004. He averaged 12.0 points, 7.0 rebounds, and 2.0 blocks against the Celtics in the 2008 Eastern Conference Finals.

Wallace has also earned a reputation for being an emotional player. He has been suspended for exceeding the limit of 16 technical fouls in a season.