George Groves overcame some blood and some rust tonight in San Jose, stopping Francisco Sierra in the sixth round on the Showtime card at the HP Pavilion.

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Groves (15-0, 12 KO) had trouble denting the bigger Sierra (25-6-1, 22 KO) for a while, but was also able to mostly dictate the action and largely outbox the tough Mexican, and BLH had Groves up 49-46 when the fight ended. It was a four-shot combo of clean punches that put Sierra down in the sixth round, and when the fight continued, Groves charged in, threw more bombs, and the towel was thrown in.

Groves' potential upcoming date with Kenny Anderson may have been affected tonight, however, as the young Brit was cut outside of the right eye by a headbutt in the third round. It bled heavily, but his corner did a good job and it never became a major factor after they got to work on it. Still, it's a wound that has to heal.

The official judges had it 49-46, 49-46, and 48-47 at the time of stoppage, all for George Groves.

Our live coverage of the Guerrero vs Aydin card continues, with a junior middleweight fight between Hugo Centeno and Ayi Bruce.