Julio Cesar Chavez Jr. recovered from a slow start due to leg cramps and stopped Andy Lee at 2:21 of the seventh round Saturday night to retain the WBC middleweight title.

A right uppercut by Chavez snapped Lee's head upwards and sideways and Chavez connected on a barrage of punches before referee Laurence Cole intervened and waved an end to the fight.

With the victory, Chavez (46-0-1, 32 KOs) put himself in position for a title-unification fight with recognized world middleweight champion Sergio Martinez.

Chavez began tentatively, not even throwing his first punch until 75 seconds had elapsed in the first round, and was initially outboxed by Lee (28-2), a much taller challenger than Chavez had previously faced. But as the next two rounds passed, the Mexican champion began to stalk Lee, blasting him with right-cross counterpunches.

After the bout, Chavez's promoter Top Rank announced that the Mexican fighter would take on Sergio Martinez of Argentina in a middleweight superfight on Sept. 15.

Adamek gets the official nod

Tomasz Adamek unanimously outpointed Eddie Chambers in a 12-round bout Saturday night in Newark in a heavyweight bout.

Adamek, a Polish fighter who lives in Kearny, N.J., has won two straight fights after losing a WBC heavyweight title fight to Vitali Klitschko last September in Poland.

Adamek improved to 46-2, receiving winning scores of 116-112, 116-112 and 119-109.

Chambers, who lost to Wladimir Klitschko for the IBF and WBO heavyweight crown in March 2010, was fighting for the first time since February of 2011, missing two scheduled bouts due to injury.

With files from CBCSports.ca