The midfielder has started onlyone of Barca's last five matches and his influence on the team has started to wane following the resurgence from Ousmane Dembele, Ivan Rakitic and Arthur.
Brentford goalkeeper Mark Flekken had earlier made an excellent one-handed save to deny Rasmus Hojlund but was beaten by substitute Mount before Ajer's late heroics.
At a team full of superstars, and from a country where Luka Modric gets all the praise, Ivan Rakitic has managed to be an underrated serial title winner. For his Barça coach however, he couldn't be any more important.
Youri Djorkaeff, Ivan Campo, El Hadji Diouf - love him or hate him, he was instrumental to what we achieved then, Fernando Hierro and Hidetoshi Nakata from Japan.
Maximum Tension The Count Basie Orchestra Directed By Scotty Barnhart - Basie Swings The Blues Vince Mendoza & Metropole Orkest - Olympians Mingus Big Band - The Charles Mingus Centennial Sessions Best Latin Jazz Album Eliane Elias - Quietude Ivan