Dundee manager John Brown believes his side have cranked up the pressure on St Mirren with their 1-0 victory over Hearts.
Ryan Conroy's deflected 30-yard free-kick earned the Dark Blues their third consecutive victory and put them eight points behind the Buddies with three Clydesdale Bank Premier League games remaining.
Dundee could, however, be relegated without kicking a ball as St Mirren face Hearts at Tynecastle next Saturday, 24 hours before Dundee host Aberdeen.
"I think you will be smelling it (fear) coming from them," said Brown. "They are going to Tynecastle and it's never an easy place to go.
"So unless they have Old Spice to cover it then I think it will be an interesting weekend.
"It was a great day, it takes it another week. For the fans today, it was fantastic.
"Hearts put in a great shift with 10 men and if they do that with 11 men against St Mirren, you never know, we might take it another week."
Nicky Riley will be suspended next week after he was sent off in the last minute and the influential Gary Harkins missed out through injury.
"We think Gary has a cracked rib," Brown said. "It was through a challenge with big Steve (Simonsen), the goalkeeper, on Thursday but that's what we do in training.
"It's contact, you can't take that out the game. Hopefully he might be there (next week) but I would think he might be out for the rest of the season."
Brown added: "Nicky will learn by his mistake. It was a silly thing to do but we are not going to criticise too much, there was a lot of emotion out there.
"It was handbags, I think he raised his hands into his face. The referee was right but I remember the days you used to give out right hooks and it was still okay."
The 37-year-old striker, who announced his retirement on Friday, marked his 395th and last League game by taking his tally to 149 with a penalty and a typically cool finish with Jay O'Shea and Marc Richards also getting on the scoresheet.
Lester led Chesterfield out but it was O'Shea who sparked the game into life with a spectacular 25-yard shot into the top left corner in the 22nd minute.
Richards headed in a free-kick in the 31st minute before Lester gave the home fans the goal they had come to see when he converted a 34th minute penalty after he was tripped by Jordan Moore-Taylor.
Exeter rarely threatened Chesterfield and they were four down on the hour when Lester was put through to place a right foot shot into the bottom corner from 12 yards.
Lester made his exit to another standing ovation 15 minutes from the end when he was substituted and Richard O'Donnell denied Exeter a consolation with three smart saves in the closing minutes.
