A teenager lost three teeth and was treated for facial injuries after being punched in an attack outside a Leicestershire pub.
The 17-year-old was hit as he ran towards friends on Church Street, Rothley, after leaving a nearby pub, at 2300 BST on 14 May.
Police said he will have to undergo extensive reconstructive dental work.
The "nasty attack" is being linked by officers to a row in a pub car park earlier in the evening.
Any witnesses to either incident have been urged to come forward.