A man was taken to hospital with a broken eye socket after an attack in Brighouse.
The 32-year-old victim was on Thornes Park on Wednesday evening when he was assaulted.
The attack comes after a man suffered a broken jaw during an assault on Huddersfield Road in Brighouse.
The victim had been approaching the junction with Millroyd Street on December 28 when he was hit from behind.
Anyone with information about either assault should call Calderdale CID on 01422 337086 or CrimeStoppers, where information can be passed on anonymously, on 0800 555111.