Grealish has not been involved in any of the Citizens' last three Premier League matches since sustaining a muscle problem in the first half of a 3-1 Champions League win against Copenhagen earlier this month.
Gvardiol, meanwhile, has been nursing an ankle ligament injury which has forced his to miss each of City's last five games across all competitions.
Guardiola, who initially suggested that both players would be sidelined for two to three weeks, has since provided a brief yet positive update on the Citizens duo ahead of Monday afternoon's first-team training session.
"[Grealish is] good. [Gvardiol is] good too," Guardiola said at a press conference on Monday. «I don't know [if Gvardiol will play]. He's training without much pain.
»Still he didn't train with us but he's on the verge to come back. We have training this afternoon, but I think everybody's fine."
One other first-team player Man City are sure to keep an eye on is star playmaker Kevin De Bruyne, who recovered from «niggles» in his hamstring to make a cameo appearance off the substitutes' bench in Sunday's 1-0 win at Bournemouth in the Premier League.
It remains to be seen whether De Bruyne, who was sidelined for five months earlier this season with a torn hamstring before making his long-awaited comeback in early January, will be considered from the start against Luton.
After registering back-to-back 1-0 wins over Bournemouth and Brentford in the Premier League to move to within one point of leaders Liverpool, Guardiola is expecting another
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