LOS ANGELES -- Dodgers manager Don Mattingly said Jerry Hairston is still in a lot of pain and surgery on his left hip could be an option for the veteran utility man.

He said the team originally thought Hairston would be out for only 15 days, but now it appears it could be much longer.

"Jerry has not really responded well," said Mattingly, who added Hairston is debating his options.

Hairston hit the disabled list on Aug. 12 with left hip inflammation after being bothered for weeks.

Dodgers activate De La Rosa from DL, option Guerra

LOS ANGELES -- More than a year removed from Tommy John surgery, Rubby De La Rosa was reinstated from the 60-day disabled list on Tuesday afternoon. In a surprising corresponding move, the Dodgers optioned reliever Javy Guerra to Triple-A Albuquerque.

De La Rosa came back quickly after undergoing Tommy John surgery on Aug. 9, 2011, and manager Don Mattingly said the right-hander would pitch out of the bullpen for the rest of the season instead of being used as a starter. He went 4-5 with a 3.71 ERA in 13 appearances (10 starts) for the Dodgers last season, and the team still views him as a starter after this year.

De La Rosa, who got the call Tuesday morning while in Rancho Cucamonga, said he didn't expect to be back this soon. He said he has hit 99 mph on the radar gun, and he is 100 percent sure he'll be able to throw 100 mph again.

"He's a power arm," Mattingly said. "He's a guy that is swing-and-miss out of the gate, especially in an inning situation."

He threw three scoreless innings in the Arizona Rookie League and nine more with a 1-0 record while rehabbing with Class A Rancho Cucamonga. Mattingly said he plans to work him back carefully out of the bullpen and not just throw him into a tough situation late in a game.

To make room for the 23-year-old righty, the Dodgers sent down Guerra, who went 2-3 with a 2.66 ERA and eight saves.

Guerra entered the season with high expectations as the Opening Day closer. After struggling through April with a 1-3 record and a 6.10 ERA, Guerra was replaced by Kenley Jansen in the closer's role.

Since giving up seven runs in April, Guerra has surrendered only six runs in 33 2/3 innings. He hasn't given up a run in 8 2/3 innings through seven appearances in August, and the last run he allowed was on July 26.

However, Mattingly said the team wanted Guerra to spend the next week or so working on his command before coming back to the Dodgers when the rosters expand in September. In his last outing on Saturday, Guerra walked two batters in one-third of an inning.

"We'll give him 10 days here to try to put some finishing touches and get back in a groove as far as being able to throw strikes without the pressure of this pennant race right now," Mattingly said.

Mattingly confident Kemp can quickly snap slump

LOS ANGELES -- Typically when Matt Kemp goes on an extended streak, it's of the hot variety. So when he goes 0-for-19, concerns arise.

Manager Don Mattingly has chalked it up to simply trying to do much with a need to just get back to what has worked in the past before this slump began. He said he's slightly concerned, but he knows with someone as talented as Kemp that things could pick up with one at-bat.

"It's that inch away," Mattingly said about how close the 27-year-old is to getting back in a groove. "As a player when you are in an 0-for-19 [slump], you feel like it's three feet away. We have to be careful to keep him from doing anything drastic. He just needs to keep working and putting days behind him. The 0-for-19 at this point, he can't get it back. It doesn't matter anymore."

After Kemp went 0-for-4 in Monday's loss to the Giants, Mattingly said the center fielder has been a little impatient swinging at the ball out of the strike zone. On Tuesday, he said Kemp needs to regain his confidence and that every player goes through ups and downs.

"It's the next 19 we are worried about," he said. "You can't let the last 19 mess you up."

Lilly hopes to be back with Dodgers in September

LOS ANGELES -- Ted Lilly was scheduled to throw two bullpen sessions -- Tuesday and Friday -- before heading out to make a couple more rehab starts. He is hopeful he will be back with the Dodgers by Sept. 1.

Lilly has been on the disabled list since May 24 with shoulder problems and he has had a rocky rehab along the way at times.

The left-hander was scratched from his weekend start with Class A Rancho Cucamonga and tests on Monday with the team doctor came back looking good, the veteran said.

Manager Don Mattingly and Lilly both said the plan going forward would be for Lilly to throw out of the bullpen, a role the lefty said he is comfortable with.

As for the last time he pitched from the bullpen: "It's been a long time," Lilly said.

Worth noting

• Infielder Justin Sellers, who has been on the disabled list since May 23, will have low back surgery on Thursday performed by Dr. Robert Watkins Jr.