Delaney began his professional career with the Parramatta Eels. He scored a try on his first grade début against St. George Illawarra in 2005 as the club won the Minor Premiership that year. He went on to make 18 appearances in total for the Eels, scoring 4 tries. His final game for Parramatta was their 12-6 qualifying final loss to Melbourne.
After limited opportunities at the Parramatta, Delaney joined the newly formed club the Gold Coast Titans for the 2007 NRL season. Delaney scored 14 tries in 62 games during his three seasons with the Titans. In 2009, his final season at the club, he helped the team finish in 3rd place in the regular season ladder, which meant the Gold Coast Titans qualified for the play-offs for the first time. Unfortunately for Delaney, a hamstring injury meant he missed the end of the season. He watched from the stands as the Gold Coast crashed out of the play-offs, 27-2 to eventual finalists, & former club, the Parramatta Eels.
Delaney signed a three-year contract with the Leeds Rhinos, starting in 2010. He was signed as a replacement for Rugby Union bound Lee Smith, who had signed a contract with the London Wasps. Delaney made his unofficial début for Leeds in Matt Diskin’s Testimonial Game at Headingley against the Bradford Bulls. Delaney scored the match winning try in a 12-10 victory. Delaney's official début came on the opening night of the 2010 Super League season against the Crusaders. He scored a try in the 34-6 victory. Delaney made 30 appearances & scored 10 tries during his first season at the Rhinos. He played in the 2010 Challenge Cup Final defeat by the Warrington Wolves at Wembley Stadium. New Leeds coach Brian McDermott started Delaney in the back-row for the first time in his Rhinos career in the second game of the 2011 season away against Hull F.C. Delaney impressed in his new role but unfortunately suffered an ankle injury which ruled him out for approximately six weeks. Delaney returned from injury and continued to impress in the back row. That year 2011 Delaney went on to win his first Grand final for Leeds playing at second-row forward. His first 3 years saw him play in three successive Challenge Cup finals but Leeds lost all three to Warrington and Wigan. He played in the 2011 Challenge Cup Final defeat by the Wigan Warriors at Wembley Stadium. He played in the 2011 Super League Grand Final victory over St. Helens at Old Trafford. He played in the 2012 Challenge Cup Final defeat by the Warrington Wolves at Wembley Stadium. He played in the 2012 Super League Grand Final victory over the Warrington Wolves at Old Trafford. Delaney played in the 2014 Challenge Cup Final victory over the Castleford Tigers at Wembley Stadium. In 2015, the Leeds Rhinos made history by going on to win the treble. He played in the 2015 Super League Grand Final victory over the Wigan Warriors at Old Trafford. A facial injury sustained while playing in July 2018 required surgery and at the end of the 2018 season Delaney left Leeds to join Championship side Featherstone Rovers for whom he was set to play in the 2019 Championship. However a reoccurrence of the injury necessitating further surgery in a pre-season friendly against Halifax prompted Delaney to announce an end to his playing career in February 2019.
