If he passes a medical, Forster will compete for a place with Scott Bain - currently sidelined with a dislocated thumb - and Craig Gordon.

The 31-year-old has fallen out of favour at Southampton.

Forster won three league titles and two Scottish Cups in a four-year spell at Celtic under current boss Neil Lennon.

He spent two seasons on loan at Parkhead before joining on a permanent deal for £2m from Newcastle United in 2012.

In total Forster made 197 appearances, as well as winning the first of his six England caps, at the Scottish champions.

The keeper has thee years left on his Southampton contract but has played just once for the Premier League club since December 2017 and has been allowed to leave having dropped to third choice behind Angus Gunn and Alex McCarthy.