The French midfielder ended the match with the best passing accuracy of any player in the final third and showed a now trademark willingness to put his body on the line for the ball.
The performance and attitude from Guendouzi left Fabregas, who was watching the match closely despite now playing for Monaco, adamant he has a bright future.
"Gotta love Guendouzi. Can play good or not so good but always shows up in difficult moments at such a young age," Fabregas said on Twitter.
"Big future ahead of him at Arsenal."
— Cesc Fàbregas Soler (@cesc4official) September 30, 2019
The 20-year-old made 33 Premier League appearances for the Gunners last season and recently earned a surprise call up to the France national team.
Former England manager Sam Allardyce also heaped praised Guendouzi's consistency and believes he's playing well beyond his age.
“What a find,” Allardyce said on The Alan Brazil Sports Breakfast.
“He’s going unrecognised and under the radar which is a good thing for him at his age, but he was thrown in the deep end last season and this year has got even better.
“He’s probably never going to be man of the match, but the consistent level of his possession, where he pops up into space at his young age, and [his ability to] keep the ball is very, very impressive.”
Arsenal coach Unai Emery has been impressed with the midfielder's attitude but believes he still has plenty of improvement left in him.
"With Matteo, last year when he came here he progressed and he is progressing," Emery said following Arsenal's win over Aston Villa.
"Really I like that spirit he has, he has talent but above all his attitude, his energy, his commitment and his behaviour.
"He's one player who is angry when he is not playing but I like that. I like that player because when they are angry they are asking you to play, when you decide that they play today they know they have a commitment to give what you need and he is one player, he is improving.
"I want to be calm with him, he is humble and continuing improving and growing up with us."
Guendouzi wasn't the only young Arsenal player that impressed Fabregas on Monday with Bukayo Saka, who set up Pierre-Emerick Aubameyang's goal, also standing out to the Spaniard.
"Saka is a player. 18 years old showing great maturity," he wrote.
Making just his third Premier League appearance, Saka started up front for the Gunners and didn't look out of place alongside Aubameyang and Nicolas Pepe.