SAN DIEGO – The off-duty Coronado police officer who shot former Chargers linebacker Steve Foley testified Tuesday that he fired his gun after Foley and a female passenger had him “cornered” in a Poway cul-de-sac.

Officer Aaron Mansker, 24, testified in the trial of Lisa Maree Gaut, who is charged with assault with a deadly weapon on a peace officer and driving under the influence in connection with the events of Sept. 3.

Mansker said he followed Foley's 1971 Oldsmobile Cutlass from Balboa Park to Poway around 3 a.m. in his personal vehicle because he thought the driver was drunk.

Mansker said Foley and Gaut exited the vehicle multiple times as the officer followed Foley's car northbound toward Poway.

Once on Travertine Court, Mansker said he backed up and drove up a hill, only to find out it was a dead end.

Mansker testified that he turned his car facing downhill, and saw Foley walking up the hill with Gaut driving the Oldsmobile right behind.

“He's now got me cornered,” Mansker told a police dispatcher.

Moments earlier at the bottom of the hill, Mansker said Foley had walked toward him “like he had some business to conduct.”

The officer said he decided to discontinue following Foley's car and drove up the hill because the “situation had gotten too out of hand.”

“Where were you going?” prosecutor James Koerber asked the officer.

“Home,” Mansker said.

As Foley and Gaut approached by foot and car at the top of the hill, Mansker said he yelled that he was a police officer and for them to stop.

Mansker said he fired a warning shot into a dirt berm because Foley had earlier said he didn't believe the officer's gun was real.

The officer said Gaut drove the Oldsmobile around Foley and came straight at him, so he fired two shots at the hood of the car, causing it to crash into the front yard of a home.

Foley appeared at the front of Mansker's car and reached for his waistband and lifted up his shirt, the officer testified.

“I thought he was going to draw a firearm ... and I wasn't going to be going home that night,” Mansker testified.

Mansker said he noticed one shot hit the football player.

“He said, 'You just shot me in the knee,”' Mansker testified.

He said he fired three more rounds at Foley when he saw him reach into his waistband again.

Mansker said Gaut repositioned Foley's car and had it pointed right at him, revving the engine.

Sheriff's deputies arrived on the scene and got Gaut out of the car when she couldn't get the vehicle in park, the officer testified.

Gaut, 26, faces up to five years in prison if convicted.

Defense attorney Raymond Vecchio will cross-examination Mansker on Wednesday.

Foley, 31, is charged with two counts of driving under the influence. He is scheduled to stand trial May 7.