The incident in question occurred late in Phoenix's loss to Memphis, as a shoving match broke out and Len vacated the sidelines to get involved.
Len has appeared in 51 games this season, averaging 7.2 points, 6.3 rebounds and 1.3 blocks per contest.
The former No. 5 overall pick out of Maryland has primarily served in a bench role behind starter Tyson Chandler.
With Len out for Friday, the Suns will be without their No. 2 rebounder and one of only two true centers on their roster.
Chandler will likely play added minutes for the 16-37 Suns, while Alan Williams may feature more prominently alongside forwards Jared Dudley and Marquese Chriss.