The Norwegian centre-back eschewed a week-long trial with the Merseyside club in favour of heading down to the south coast club for talks before sealing a move.
And, ahead of a possible Premier League debut at Solkjaer's former haunt Old Trafford on Wednesday, the 24-year-old has claimed his old manager influenced his decision.
He told reporters: “I never came close to joining Liverpool because Southampton felt right for me.
“There was a lot of interest from the Premier League but after coming here and speaking with the chairman I really felt wanted.
“Ole was very supportive of the move and I spoke with him a lot before coming here. He really wanted me to take this opportunity.”