LONDON — Kell Brook won his second defense of the IBF welterweight belt to stay undefeated, while fellow British boxer Anthony Joshua enhanced his burgeoning reputation in the heavyweight division with a second-round stoppage of experienced American Kevin Johnson.

Brook extended his record to 35 wins by outclassing Frankie Gavin in a one-sided, all-British fight stopped late in the sixth round.

In other world title fights at London's O2 Arena, Jorge Linares of Venezuela retained the WBC lightweight belt by stopping Kevin Mitchell in the 10th round and Lee Selby of Britain took the IBF featherweight belt off Russia's Evgeny Gradovich after an eighth-round technical decision.

Joshua — a gold medalist at the London Olympics in 2012 — stopped Johnson 83 seconds into the second round for his 13th straight professional victory.