Manchester United's reserve midfielder Phillip Mulryne joined the Canaries on transfer deadline day (25th March 1999). A Northern Ireland international, Philip couldn't break into the United first team and so leapt at the chance to join Norwich for £500,000

At the time of his transfer, Phillip had played 6 times for both Northern Ireland and Manchester United. Indeed, he made his debut for the Irish before he broke into the United first team. His full international debut came in February 1997 against Belgium whilst he made his United debut against Ipswich in the Coca Cola Cup the following October. He has also played for the Northern Ireland Under 21s partnering Adrian Coote. Phillip scored his first goal for the Canaries in their 1-0 victory at Grimsby and got his second in the 2-2 draw with Tranmere, a game in which he captained the Norwich team.

Phil missed most of the 1999/2000 season after a horrific foul by Blackburn's Christian Dailly in the clash between Rovers and the Canaries at Carrow Road on 28th August 1999. He returned to competitive action on 28th March 2000, ahead of schedule, when he played the final 30minutes of the Reserves' defeat at Millwall. Phil then made a surprising appearance for the first team at Portsmouth on 8th April, playing the first hour of the match before being replaced by Darel Russell. His rehabilitation was completed when he was named in the Northern Ireland squad to face Hungary on 26th April 2000. Phil scored his first international goal against the Czech Republic in June 2001 and was rewarded with call-up for the ties with Denmark and Iceland in September 2001

In February 2002, the media speculated that Phil would join Ipswich Town. Days later Norwich confirmed that Phil had rejected a "substantial new contract" and would thus be free to depart Carrow Road on a Bosman free in the summer of 2002. Nigel Worthington suggested that he might try to sell Mulryne to at least recoup some of the £500,000 paid for the midfielder now valued at £2million. The next club to be linked with him was Leeds United, followed by Charlton Athletic on 26th March 2002. On 19 May 2002, the Sunday People claimed that Crystal Palace were hoping to sign the midfield schemer whose penalty miss contributed to Norwich's Division One Play Off Final defeat to Birmingham. A new three year contract with Norwich was eventually signed on 5th June 2002 with Phil citing the support of the Norwich fans and the ambition of the club as the motivation for his decision to stay (so it had nothing to do with the fact that no other clubs were really interested in signing him and playing him regularly !)

Phil made 37 appearances during 2002/03 and finished second highest scorer with 8 goals. The following campaign just resulted in 3 goals from 14 starts. Out of favour during Norwich's Premiership campaign, he was the subject of an enquiry from Gary Megson's Nottingham Forest in March 2005.

Phil left Norwich at the beginning of May 2005, cancelling the contract by mutual agreement. He joined Cardiff City on trial towards the middle of July 2005, playing for them in a pre-season friendly against Accrington Stanley on 16th July 2005. He signed for them on 29th July along with West Brom's Darren Purse and Wolves' Kevin Cooper. He quicky fell out of favour at Ninian Park and by the spring of 2006, was expressing his views that he would be departing Cardiff in the summer of 2006. The first club to be linked to him were Bradford City.

Released by Cardiff, Phil appeared for Ipswich Reserves at the end of August 2006. The following month, he joined Brighton on trial. He has since had trials with Legia Warsaw and Barnsley - the latter cut short through injury. He then appeared in January 2007 on trial with Leyton Orient. He joined Orient on a short-term contract but was released at the end of the 2006/7 season. He joined Bournemouth on trial in July 2007 playing in four pre-season friendlies. Rejecting Bournemouth's offer of a short-term contract, Phil joined St Mirren on trial during the second week of August 2007. He was then reported to be on trial with Aberdeen. In early September 2007, he was training with Norwich City to keep his fitness up.

On 25th October, it was announced that Mulryne, who had been training with Yeovil, would sign a short-term contract with Kings Lynn. He was released by the Linnets in December 2007

It was announced on 14th March 2008 that Mulryne was training with Cliftonville. On 26th June 2008, Northern Irish side Linfield had invited Mulryne to train with them after a move to the USA broke down. Mulryne said "“I haven't had much success getting a club in England so I've decided to come home and give the Irish League a go. I haven't played much in the last two or three seasons so hopefully I can get sorted and get my career going again. The Irish League is a good standard and I still feel I have plenty to offer a club. I've been training on my own this summer but with a good pre-season under my belt I'm sure I'll be ready.”

In July 2009, it was revealed that the Bishop of Down and Connor had invited Phil to train for the Roman Catholic Priesthood. In seven years, he could be ordained as a priest for the diocese. His mother, Sally, confirmed her son's vocation to a Sunday newspaper.She said it was a "big decision" for him but that he would be starting at the end of August 2009. This was confirmed by Paul McVeigh in January 2012 who had visited Mulryne in Rome where he is training. He spent two years studying philosophy at Queen’s University Belfast and at the Maryvale Institute. He then went to the Pontifical Irish College, Rome, to study theology for one year at the Gregorian University before discerning a call to religious life.

On 29th October 2016, Mulryne was ordained as a deacon by the Archbishop of Dublin, Diarmuid Martin. The 38-year-old is a member of the Dominican Order and is expected to be ordained as a priest next year.

He was ordained as a priest in the Dominican Order on 9th July 2017