ANOTHER HILL LEFT TO CLIMB PITCHER STRAINS RIB CAGE IN LOSS TO ATHLETICS OAKLAND 5, ANGELS 2.

Byline: Billy Witz Staff Writer

ANAHEIM - The Angels' most pressing questions are no longer how will their young pitchers hold up, or how will they respond to rookie manager Mike Scioscia, or how long can they stay in the AL West race.

The question they're grappling with is who will it be today?

One day after shortstop Gary DiSarcina - ``the glue to the club,'' according to Scioscia - was placed on the disabled list, the Angels may have lost staff ace Ken Hill after he strained a muscle in his rib cage early in Tuesday's 5-3 loss to Oakland in front of 15,308 at Edison Field.

Hill sank to his knees and buried his face in the ground after throwing a 2-0 pitch to Miguel Tejada in the third inning. He stayed there until he was helped to his feet and escorted off the field by trainer Ned Bergert and Scioscia without even attempting to stay in the game.

The 34-year-old Hill has been injury-prone of late - mostly due to an arthritic right elbow. He's been sent to the disabled list four times in the previous three seasons and underwent elbow surgery in 1998.

If Hill's injury is serious, he'll join two other pitchers - Jason Dickson and Tim Belcher - on the disabled list.

So, even though the Angels are playing with renewed enthusiasm and vigor under Scioscia, it's beginning to look like last season as far as injuries are concerned.

Adding insult to injury was the way Oakland right-hander Gil Heredia tamed the Angels. He shut them out on four hits until Darin Erstad led off the eighth inning with his fourth home run, a drive to center field.

Athletics manager Art Howe then closed his eyes and turned the ball over to his bullpen, which had blown leads of four, eight and five runs in the past week.

But Mike Magnante and Jeff Tam held the Angels in the eighth before Jason Isgringhausen finished the job in the ninth.

Heredia, who walked two and struck out two, was threatened only a handful of times.

He stranded two runners in the second when he got Bengie Molina and Benji Gill on fly balls. He allowed a two-out double to Troy Glaus in the fourth, but retired Orlando Palmeiro on a groundout. And in the seventh, Heredia retired Molina and pinch hitter Scott Speizio to leave two more runners on base.

Hill, who began the game with a 3-3 record and a 7.39 ERA, struggled in this one, too. He left the bases loaded in the first when he got Jeremy Giambi to pop out. But in the second, after Ramon Hernandez bunted runners to second and third, Terrance Long followed with a one-out RBI single to left.