And the input of Robertson, who smashed 27 competitive goals past Hibernian during his illustrious Tynecastle career, has been hailed by Glen as a real confidence booster for himself and his fellow strikers.
"We pretty much just did shooting the whole session," said Glen of last week's tutorial.
"He's talked to us, he's told us what he used to do.
"Last week, when we did our training, when we were doing the shooting, it got our confidence up.
"That's what he's looking to do and hopefully he'll do that again."
After his initial visit to the club's Riccarton training base, Robertson was back in on Thursday and Glen was expecting plenty of tales of the 45-year-old's derby scoring feats.
"I imagine he'll stick that in somewhere!" said Glen.
"It's a massive help for us because of his record."
Former Hearts manager Robertson reportedly owns a T-shirt which commemorates the club's 21-game unbeaten run in Edinburgh derbies during his time as a player.
"I've never seen it - I'll ask him," said Glen, who acknowledged there was a need to do something about the club's problems finding the net this season.
"We can't sit here and blame anyone else for us not scoring.
"At the end of the day, it's down to us.
"If we can't score goals then obviously our confidence is going to get down.
"We've just got to try to keep our heads up and keeping trying our best to get goals."
Glen has scored only four goals in his three-year professional career but one of those did come on his Edinburgh derby debut when Hearts won 2-0 at Easter Road in the Scottish Cup.
"Obviously, that was a great experience, going to Easter Road and winning the game there and getting a goal," Glen said.
"If I'm involved at the weekend, I'd look to do the same as well."
Glen revealed that, as well as the sessions with Robertson, the return of manager Jim Jefferies and his assistants Billy Brown and Gary Locke had also given him a boost, admitting he had been feeling low during an injury-hit spell under former boss Csaba Laszlo.
He said: "My confidence was down but now that the gaffer, Billy and Lockey have come in, they're doing their best to get my confidence back, doing extra training and getting my fitness back.
"I'm delighted that they've come in and I feel better about myself.
"The atmosphere's changed; everyone's a lot happier."
Saturday's match will be Jefferies' first derby in charge for almost a decade and as a lifelong Hearts fan and former player as well, the 59-year-old looks certain to be fired up for the occasion.
But Glen said: "You don't really need anyone to get you hyped up for a derby game.
"If you're not hyped up already then you shouldn't really be there.
"Because obviously it's a massive game for the club and the fans."
Saturday's result could be crucial to Hearts' hopes of finishing in the Scottish Premier League top six, with St Johnstone breathing down their necks in seventh place.
But Glen prefers to look at the 10-point gap to the Jambos' arch-rivals, who are fifth.
Asked if Hibs can still be caught, he replied: "I'd like to say it was possible, yeah."
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