Ashton equals Top 14 try record
Ashton, who will turn 31 on Thursday, matched the record of Fiji's Napolioni Nalaga, set in 2008-2009 while playing for Clermont.
He reached the mark in the 19th minute of Sunday's game as Toulon ran in seven tries which condemned defending champions Clermont to missing out on the play-offs this season.
Despite being on a run of three successive wins in March and welcomimg back scrumhalf Morgan Parra (out since January) and flyhalf Camille Lopez (injured in October), Clermont were ripped to shreds by the three-time European champions.
Toulon, shocked 26-29 by Oyannax last weekend, were already 35-0 up by the break and romped home with Eric Escande, Romain Taofifenua, Josua Tuisova, Malakai Fekitoa (two) and Mamuka Gorgodze joining Ashton on the scoresheet.
"We can't say that we expected this, scoring 49 points but it's what we're aiming for," said Toulon coach Fabien Galthie.
"We must remember how we played in the first half – it was remarkable."
Clermont can still salvage their season when they face French rivals Racing 92 in the European Champions Cup quarterfinals next weekend.
However, coach Franck Azema admitted there is plenty of work to do this week.
"Conceding 50 points before a European Cup quarterfinal is humiliating. I had trouble doing my job this week and failed to motivate the guys. We are not going to hide – everything was bad."
Racing moved into second place in the table, five points behind leaders Montpellier, with a come-from-behind 24-22 win at fellow play-off hopefuls Lyon.
Racing were 12-6 down at the interval but rallied in the second period with Baptiste Chouzenoux and South African fly-half Pat Lambie scorig tries.
Lionel Beauxis scored all of Lyon's points with a converted try two minutes from time and five penalties.