He was sold to Conference Premier rivals Wrexham in April 2010; in doing so he resigned his position in a car factory to become a full-time professional footballer.

Histon enjoyed a successful 2004–05 campaign and were crowned champions of the Southern League Premier Division, resulting in promotion to the Conference South.

[5] Histon then went on to dominate the division in the 2006–07 season, racking up 94 points to secure the Conference South title, with Knight-Percival contributing five goals from 28 games.

Histon qualified for the FA Cup in 2008–09, knocking out League One sides Swindon Town and Leeds United in the opening two rounds with two 1–0 wins, before finally losing 2–1 to Swansea City.

[10] He went on to score ten goals from 50 matches as Histon posted a third-place finish in the Conference Premier, though they were beaten 2–1 on aggregate by Torquay United in the play-off semi-finals.

[14] Knight-Percival scored four goals in 34 games in 2010–11, helping Wrexham to the play-off semi-finals, where they lost out 5–1 on aggregate to Luton Town after losing the first leg at the Racecourse Ground 3–0.

[26] On 23 September, he received a red card against Milton Keynes Dons in the 7th-minute, following an elbow on Patrick Bamford; Peterborough were reduced to nine men when Mark Little was also sent off in the 76th-minute, but they managed to hold on to win 2–1.

[29] Just two days after Leyton Orient defeated Peterborough in the second leg of the League One play-off semi-final,[30] Knight-Percival was among five players released by manager Darren Ferguson in May 2014.

[31] Knight-Percival joined Shrewsbury Town on a free transfer on 22 May 2014; the "Shrews" had just been relegated into League Two and new manager Micky Mellon signed a further 14 new players to reinvigorate the club.

[32][33][34] He made his debut on the opening day of the 2014–15 season, playing left-back in a 2–2 draw away at AFC Wimbledon,[35] and scored his first goal at the New Meadow in a 3–1 victory over Cheltenham Town on 11 October.

[34] However he was sent off for two bookings in a goalless draw away to Luton Town on 8 January,[37] and the following month suffered a cruciate knee ligament injury which ruled him out for the rest of the season.

[39] After making his comeback in a Football League Trophy first-round match against Oldham Athletic,[40] he scored the winning goal in a 1–0 victory over Southend United in September and picked up the nickname 'Rolls-Royce' for his assured performances.

[43] Town finished one place above the relegation zone and reached the fifth round of the FA Cup, overcoming Championship opposition in Cardiff City and Sheffield Wednesday, before bowing out of the competition with a 3–0 home defeat to Premier League giants Manchester United.

[57] In May 2019, following Bradford City's relegation to League Two, new manager Gary Bowyer named as Knight-Percival as of 11 players to be released upon the expiry of their contracts at Valley Parade.

[60] However Knight-Percival failed to build a good understanding with Byron Webster and featured just twice after Chris Beech replaced Pressley as "Blues" boss in November.