Lineham's position as a junior with York RUFC was in the back row, he was equally adapt at number 8 or openside-flanker, but has played as an inside-centre for York RUFC, and more recently as a when he converted to rugby league. Lineham joined York RUFC under 15s in September 2006 as a raw young talent with excellent speed and strength. He quickly became a regular in the York team, going on to represent North Yorkshire that same season. Lineham's second season with York was an even better one than his first, he was York's top tryscorer at the end of the season. Lineham really got heads turning and people talking about him and his performances, which led to a Yorkshire call up at blindside-flanker part way through the 2007-2008 season. Lineham then went to York College in 2008 to study for his A-Levels, this is when he first started playing rugby league for the College's Rugby Development Centre, originally coached by the late Paul Higgins. Once again Lineham excelled for the team scoring 15 tries in 7 appearances, earning a trial with the Knights. Lineham played two trial games with the Knights reserve grade and subsequently was offered an 18-month contract with the Knights in 2009. Lineham has signed a further 1-year contract at the Knights for the season 2011 season where the Knights will be playing in the championship after last seasons promotion. Hull F.C. were believed to have approached Lineham with an offer but no contract was agreed due to Linehamneeding anterior cruciate ligamentknee reconstruction leaving in him sidelined for 9 months. Linehams first try for the Knights first team came on 2 April 2010 against Gateshead Thunder at Huntington Stadium when he ran the ball in from 50-metre. Knights boss James Ratcliffe joked: "I think I would’ve scored Tom’s try if I was 20 years younger." Lineham's talent is obvious when he was picked last minute to run in a race to name rugby leagues fastest man. Lineham achieved only 3rd place. Being the youngest in the race and less than 0.2seconds behind the winner, Lineham proved his capabilities. As well as sport Lineham is concentrating on completing a sports diploma at Selby College whilst playing professional rugby. Lineham signed for Hull F.C. in 2011. After a number of eye-catching performances in the Academy, Lineham made his first team début as a late substitute in the 32-18 derby win at Craven Park. His performance was rewarded with a starting spot in the next game at home to Salford Red Devils, where he scored two tries whilst making a notable contribution to another, in a Man of the match performance consolidating his status as one of the most promising young talents in super league. Enjoying a sparkling breakthrough season in 2013 in which he was named the Hull FC's Young Player of the Year and the Super League Albert Goldthorpe Rookie of the Year, Lineham is one of the most exciting young players to come through Hull’s ranks for some time. Earning a place in the Super League Dream Team alongside partner Ben Crooks last year, Lineham has been granted the No.5 shirt by new head coach and former mentor Lee Radford in 2014. Tipped for England Knights honours before opting for close-season surgery on a troublesome wrist injury, continued progress could see Lineham make his international bow during the next 12 months. Lineham has previously played for the York City Knights. He has also played rugby union for York RUFC. Lineham has represented Yorkshire in Rugby Union. In 2013 Lineman was awarded the Albert Goldthorpe Rookie of the Year Medal. Lineham enjoyed another outstanding season for Hull in 2015, scoring 22 tries. In 2016 he moved to play for Warrington Wolves, where he performed badly and was dropped from the team and Super League. His manager said Lineham's attitude was misaligned and he was, "lazy". Warrington then decided to play him again although his performance against Castleford Tigers on 21 May 2016 proved unimpressive. He played in the 2016 Super League Grand Final defeat by the Wigan Warriors at Old Trafford. In the last year Lineham's weight gain and consequent loss of speed has earned him the comical if not somewhat cruel nickname, "the flying pig". A nickname which he apparently endorses. He played in the 2018 Challenge Cup Final defeat by the Catalans Dragons at Wembley Stadium. He played in the 2018 Super League Grand Final defeat by the Wigan Warriors at Old Trafford. He played in the 2019 Challenge Cup Final victory over St. Helens at Wembley Stadium.
