Fraser Forster was delighted to see Celtic scoop derby day glory – but warns their win over Rangers hasn't sealed the title.
The former Hoops keeper watched on as Tom Rogic and Cameron Carter-Vickers goals claimed a 2-1 victory for Ange Postecoglou's men at Ibrox.
It has put them six points clear at the Premiership summit with six games to go this season.
Forster returned to Southampton in 2020 following a loan spell at Parkhead which culminated in an inspired League Cup victory and another league title crown.
It was the second time the 34-year-old – who was thrown back into England contention last month – had been at Celtic after initially joining on loan from Newcastle in 2010.
He would go on to have four years at the Glasgow giants before his 2014 move to Saints.
Speaking of his former side's most recent derby win, Forster says it filled him with joy as a fan, but the ultimate goal is not yet achieved.
He told Sky Sports: "I did watch it, I watch all of them. I loved my time at Celtic and I will be a supporter for life. It's a huge result.
"They showed character to come away with the three points. It's the same as ever at the top of the league, it isn't over until it's over.
"It will be an interesting run-in with plenty of points to play for. There's one more Old Firm and there is a lot of work to do to get that title over the line.
"It's a massive result, especially at Ibrox. It gives massive confidence for the Celtic lads and hopefully it kicks them on."
