The 29-year-old arrives back in the Midlands from Vanarama National League side Yeovil Town.

He signed for the Glovers after leaving Coventry City earlier in the summer of 2019.

After enjoying a run of games for Yeovil at the start of the 2019/20 season, O'Brien suffered an injury during an away win against Solihull Moors.

But after recovering, his contract with the Glovers was extended until the end of the season.

A former England under-19 international, he joined Yeovil as a free agent after being part of the Coventry side under Mark Robins that won immediate promotion back to League One in the play-off final at Wembley in 2018.

Signed by Portsmouth from Queens Park Rangers as a youngster following trials at the likes of Manchester United and Arsenal, he was an unused substitute for Pompey in the Premier League before gaining a first taste of senior football on loan at Vanarama National League South side Eastbourne Borough.

He went on to have spells with Barnet, Brentford and Dagenham & Redbridge before re-joining Portsmouth in August 2016.

He left Fratton Park in the summer of 2017 to join Coventry.