Everlast Worldwide, the boxing brand worn by Muhammad Ali, became the center of a $127 million takeover fight on Friday after a rival offer topped one agreed a day earlier.
New York-based investment firm Hidary Group sweetened its offer by 18% to $31.25 a share, after its earlier agreed bid at $26.50 a share was pipped on Thursday by a UK retailer.
Everlast had signed a "go-shop" provision allowing it to seek other suitors.
Hidary also said it would be prepared to consider a further increase if Everlast's termination fee in connection with the other deal was invalidated.
With 4.07 million shares outstanding as of April, according to Reuters data, the Hidary offer values Everlast at $127 million.
Everlast agreed to be acquired by UK sporting goods retailer Sports Direct International for $30 a share on Thursday. Sports Direct, with about 400 Sports World stores, also owns sports-goods brands Slazenger, Dunlop and Lonsdale.
Everlast's shares rocketed up 8.5% to $32, as investors anticipated the takeover price to go higher still. Sports Direct shares fell 1.2% to 181-1/4 pence.
A Sports Direct spokesman declined to comment.