Police want to speak to the man shown in this CCTV still about an incident involving a baseball bat at a pub in Hasland.
The man was in the Devonshire Arms in Mansfield Road when another man walked in and swung a baseball bat around.
During the incident - which took place in January - a reveller suffered facial injuries when he was pushed to the floor outside the pub.
Officers think the man shown in this image might have information relating to the incident and would like to speak to him about it.
If you recognise him, please call PC Dean Cutts on 101, quoting reference 17000018591.
Alternatively, send him a message online by visiting the Contact Us section of the Derbyshire Police website.
You can also call Crimestoppers, anonymously, on 0800 555 111.