The Reds boss was giving an update on the youngster as well as Alex Oxlade-Chamberlain.
The Liverpool boss was speaking ahead of hosting Crystal Palace at Anfield tomorrow.
Brewster is recovering from procedures on both his ankle and knee and will not play again this season.
That’s despite the 18-year-old returning to Melwood and running once again.
On Brewster, Klopp said: “He’s not as far as he would like to be. He’s outside training, his running looks much better since he had this other little surgery.
“He’s in a good way but it will take time. But it’s no problem, he has the time.
“We don’t have to think about him before the pre-season, I would say. He’s in a good mood.
“He’s a nice fella, really integrated in the team, but so far he couldn’t show it on the pitch.
“But our opinion about him will not change. We have to wait a little longer for him.”
Klopp was more optimistic on Oxlade-Chamberlain playing again this season though.
He explained: “He’s closer than Rhian, he’s on a very good way but it will still take time.
“Last time, I think I put a bit of pressure on the medical department but when I see him running or on the ball, it looks good, promising, close to return. But after so long out….
“No problems, no swellings, he can work on his fitness issues. I think we will see him this season.”
Liverpool take on Crystal Palace at Anfield at 3pm tomorrow.
The Reds are currently four points clear of Manchester City at the top of the Premier League table.