[4] He spent the 2004–05 season on loan with Bodajk, the reserve team of MTK, and played regularly for them in the Nemzeti Bajnokság II.

[7] He was sent-off in Chesterfield's game against Southend United on 18 February 2006, which the club unsuccessfully appealed when it was rejected by The Football Association, who issued Kovács a one-match suspension.

[8] Kovács joined York City in the Conference National on a one-month loan on 2 March 2007 and made his debut in a 0–0 home draw with Forest Green Rovers the following day.

[20] Kovács scored in his first home appearance for the team with a headed equaliser in a pre-season friendly against Premier League side Aston Villa on 15 July 2008, which Lincoln eventually won 3–1.

[24] He made his debut in a 2–0 win at Histon on 27 January 2010, scoring the opening goal with a diving header from a Kevin Nicholls corner kick.

[27] He made his Hereford debut in a 1–0 away win at Crewe Alexandra in which he scored his first goal for the club with a header from a James McQuilkin corner kick.

[32] On Kovács signing a permanent contract Luton manager Gary Brabin said "János has been a rock at the back for us since joining us again.