The much-improved 25-year old begun his career as a left-back and even on the left wing but this season has found his niche as a centre-half alongside Swedish stopper Daniel Majstorovic.
It has taken Mulgrew a while to make it at the top after he was discarded by Celtic back in 2006. Since then he tried his luck with a loan deal at Dundee United, a move to Wolves in England, another loan at Southend United and a couple of seasons at Aberdeen.
But last July, Mulgrew returned to Parkhead and has grown into a player with plenty of capabilities at the heart of defence. He said the fact he was now not just trying to get a game but trying to win a trophy was something he never imagined would happen.
"A year ago for me it was just about trying to finish the season on a high with Aberdeen," he said.
"We hadn't had a great season and my contract was up as well.
"Now at Celtic we have a lot to play for - although we just want to take it one game at a time.
"A year ago, I was concentrating on trying to get a few wins for Aberdeen and making the right decision for my career.
"I didn't want to rush into anything, so I think I made the right decision in the end. I'm just glad I waited.
"There were a couple of offers from down south and other places in Europe. But the minute Celtic were interested there was no doubt this was where I was coming.
"I grew up a Celtic fan and this is a huge club, so I was glad to get the opportunity to return."