Tony Thompson's hopes of securing a third showdown with heavyweight kingpin Wladimir Klitschko are almost certainly over after he lost to Malik Scott.
Scott was floored by a right hand in the ninth round but climbed off the canvas to secure victory in the 10-rounder via a unanimous points decision.
Veteran southpaw Thompson had hoped to use Scott as a stepping stone to secure a showdown with WBC champion Deontay Wilder.
However, the 44-year-old's dreams of turning back the clock and winning a world title are in tatters following the 98-91, 96-93 and 95-94 verdict.
Scott, who improved his record to 38-2-1, fought Wilder last year but lasted only 96 seconds against the American knock-out specialist.