AP McCoy equalled former boss Martin Pipe's career tally of 4,191 winners as he rode On the Record to victory at Uttoxeter.
The Jonjo O'Neill-trained favourite won the 32Red On The App Store Handicap Hurdle by a neck from Bangkok Pete.
"I made hard work of it," said McCoy. "The thing with me and Mr Pipe is that it's a personal thing. I hope I've driven him mad!"
McCoy is on course to become the first jockey to ride 300 winners in a season.
The 40-year-old recorded his fastest-ever half-century of winners at Worcester last month and now has 75 for the campaign.
His best tally remains 289, which he achieved in the 2001-02 season.
Pipe was champion trainer 15 times and forged a formidable partnership with McCoy before the jockey was appointed retained rider to owner JP McManus in 2004.
The Northern Irishman is the only jump jockey to have ridden more than 3,000 winners and passed the 4,000 milestone at Towcester in November 2013.
He was BBC Sports Personality of the Year in 2010, and has twice come third in the voting for the annual award.