BOSTON – Frustrated Red Sox right-hander Clay Buchholz, out since mid-June with a lower back strain, is still feeling discomfort and hasn’t been able to do more than throw off flat ground.

While Jon Lester is slated to return from the disabled list and pitch Monday, Buchholz — who last pitched June 16 — was slated to throw off the bullpen mound for the first time Friday, but instead threw in front of the bullpen. He reported progress but not enough to allow him to continue the slow process toward a return.

“I’m throwing with pretty good intensity right now,” Buchholz said before Friday night’s game. “It’s the down time after I throw that the soreness comes. It’s still got a little bit of stuff there. I think I could go out and throw a bullpen and it would feel the same (as) after I threw long-toss, since it would be the same effort level, so it would just be getting back up I think we’re going to have to work to throw a side, sit down for five minutes and get back up and throw another one. I think that’s where everything is going to come into to play.”

Manager Terry Francona, who said the decision on Buchholz not throwing in the bullpen Friday was a mutual one, said he hopes to have his pitcher throwing “maybe a bullpen Sunday or Monday.”

“It’s definitely better. It’s getting better every day,” Buchholz said. “It’s just, as I said before, I wasn’t going to do anything until I didn’t feel anything, so that’s where I’m at right now.

“It’s still got a little bit of stuff going on there. I think it’s already taken way too long for this in my mind, but I’m already on the DL so it can’t really get any worse than it was at the beginning and it hasn’t gotten any worse. It’s just slowly getting better.”

After losing his first two and three of his first four decisions, Buchholz, who hasn’t lost since April 26, went 5-0, winning his last two starts while yielding two runs in 12 innings.