Right now, of course, Glenn's priority is picking up the points for Premiership safety this season, and he is certainly not putting Les under any pressure to decide what to do beyond it.
But he saw enough nearly a fortnight ago to convince him that he could go into extra time of a long, illustrious career.
"We have secured him on a short term deal; I don't think Les has decided his future as far as next year is concerned and whether he feels he will want to retire," says Glenn.
"But if he plays like he did on Saturday for us Les is just the sort of character and human being you would want to try and keep at the club and extend his career by another 12 months.
"That is in the future and a lot depends on what happens between now and the middle of May, but if Les carries on in the manner he has started here, who knows?
"Maybe we can convince him to extend his career by a year; I am sure someone like Jermain Defoe will be really happy if he does.
"Les really epitomised against Spurs what we have been missing this season with Kanoute out, and that is important.
"It was clear that we have been without that physical presence, and with Les playing it took such a weight off young Jermain Defoe's shoulders, that instead of him being the only target up front he was able to work off Les, and because of that he had a great game and was able to twist and turn without the pressure of being the lone striker.
"It made a huge difference, and the whole point of getting Les in was that when Fredi isn't available through injury, or, as now, suspension, we are not too lightweight as an attacking team."
Another match winning performance by Les at Everton might enable him to hold off the threat to his place from Fredi, whose three match ban comes to an end this weekend.
At least Les has got history on his side, having scored 15 times against the Toffees in the past, and should he add to that tally on Saturday he will surpass the record which he currently shares with West Bromwich Albion's Derek Kevan, who played in the sixties.
Les, who scored on the opening day of the season against them after coming on as a substitute for Spurs, though more important to Glenn is not Les getting the record outright if he notches, but that three more points can be secured.
"I don't like to change a winning team, very rarely do you change a winning team, and all those players playing for the shirts know that if they play well they will keep them," Glenn says.
"Les has played in World Cups for his country, and because of attitude and mentality to help younger players, he has really gone out of his way to help Jermain, and he has responded in a positive manner.
"When we get Fredi back after the Everton game you are looking at Fredi, Les Ferdinand, and Jermain Defoe; it is quite exciting really as any two of those three would be a difficult pairing to play against."
Glenn insists the win over Spurs could have been more emphatic, though he admits they could have scored when Teddy Sheringham made an uncharacteristic miss from four yards out in the first half.
"Basically that was their one very good chance, but we felt we thoroughly deserved to be a goal to the good at half time - and we could and should have easily been two goals to the good," he says.
"But had Teddy scored in that situation we would have been very disappointed because it would have been a set play again, and we have worked so hard to eradicate conceding goals from set plays in the last three or four weeks.
"We thoroughly deserved to be a goal to the good, and we got our just rewards early in the second half with an early goal to give us that cushion of a two goal lead that we have hardly had this year."
Goal difference could become an issue now as Bolton's 'lead' in that respect has closed down to five goals following their 2-0 defeat at Liverpool last weekend.
But could it have been down to four if Ian Pearce's header, which looked to many to have crossed the line, had been awarded?
"I don't think so; it probably looked like a bad miss, but when you see the quality of the save you have to give Keller a lot more credit than he got at the time," says Glenn.
"It was a fantastic save the way he recovered to spring up in the corner where the ball was.
"He made some good saves, and Glenn Hoddle was very gracious in defeat because he knew we were the better team; he basically said that, and in his heart he knows that we probably let Spurs off lightly at 2-0.
"Thankfully we had Les in our team because I am sure had he not played for us we would have been up against him, and he would have made the game more difficult for us."
Despite a two week break from playing, the players have been training hard, and Glenn adds:
"We didn't take too much time off; it was important to keep our heads down and our noses to the grindstone.
"We have had two wins which gives us a lot to build off, but we know how tough it will be at Goodison Park against a team having a magnificent season.
"There is obviously a lot of confidence up there nowadays but we will also go up there in a confident mood and look forward to this game."