Jermain Defoe, who made way for Fredi upon his return from illness against Everton last week, is chomping at the bit to play versus the side against whom he scored the winner earlier in the season.
With Fredi himself hoping to retain his place, and Paolo Di Canio looking to impress against the team who were interested in signing him at the start of the year, Glenn is faced with a pleasant selection headache.
"We all want to play and have to deal with that," says Fredi. "You have to play well to deserve a chance to play every Saturday.
"If one of us has to not play, it has to be done.
"I think there are many ways we can play together but he has got to change the tactics and we can't afford to change all the team just because of us.
"When he needs Jermain he will play, when he needs Paolo he will play, and when he needs me the same."
Meanwhile, he hopes that fellow Frenchman Sebastien Schemmel continues the form which sees him as a strong contender to at least be in the top three of Hammer of the Year award this season.
But Fredi urges him not to take the foot off the pedal in the final quarter of the season, but to set his sights towards representing his country, if not this summer, in the not too distant future.
"He is having a great season and I am always telling him that. After the Everton game I said he has put in excellent performances like that so often this season," says Fredi.
"He has to get this ambition to play for the national team. Everybody who is French has to get this ambition even if it doesn't ultimately happen - ambition makes you improve."
He is also hoping that Laurent Courtois, who he recommended to Glenn last summer, adds to the five starts he has made thus far since his free transfer from Toulouse.
"He is a very good player and I was just a bit surprised that he hasn't played more, but I hope he will be able to play some more before the end of the season," says Fredi.