He was promoted to the assistant referees' list of the Football League in 1998, and made the step up to full referee in the League five years later.
He refereed his first FA Cup match on November 17, 2001, taking charge of the first round tie between Dagenham & Redbridge and Southport, which was settled for the home side by a Mark Stein penalty after 26 minutes.
His first match after elevation to the League list of referees was the League Two encounter at Sixfields on August 9, 2003, involving Northampton Town and Torquay, Jason Fowler scoring the only goal for the visitors.
His most notable other match was a League One play-off semi-final second leg, when Blackpool defeated Oldham by 3-1 on May 19, 2007.
On July 26, 2007, a Press release from the Professional Game Match Officials Limited, which employs Premier League referees full-time, stated that Probert had been included in the Select Group of 19 referees for season 2007-08.
Prior to this, he had been 'trialled' in the top league during the previous season, being given control of the game between Sheffield United and Portsmouth at Bramall Lane on January 13, 2007, which ended in a 1-1 draw.
Career statistics
| Season | Games | Total  | per game | Total  | per game |
|---|---|---|---|---|---|
| 2001/2002 | 10 | 33 | 3.30 | 1 | 0.10 |
| 2002/2003 | 15 | 45 | 3.00 | 2 | 0.13 |
| 2003/2004 | 28 | 82 | 2.93 | 7 | 0.25 |
| 2004/2005 | 32 | 94 | 2.94 | 7 | 0.22 |
| 2005/2006 | 40 | 127 | 3.18 | 8 | 0.20 |
| 2006/2007 | 38 | 107 | 2.82 | 5 | 0.13 |
| 2007/2008 | 37 | 82 | 2.21 | 3 | 0.08 |