Charger Rivalry Is Taken Personally : Raiders: L.A. assistant coach’s goal is to help beat the team he put together in San Diego.

Because of developments on the field and in the front office, the AFC West rivalry between the Raiders and San Diego Chargers has evolved into something especially intense.

Today’s game at Jack Murphy Stadium will mark the return to San Diego of Raider assistant coach Steve Ortmayer, who served as the Chargers’ director of football operations for three seasons before being fired Dec. 18.

Ortmayer, in effect, assembled the Charger team he hopes the 5-1 Raiders will disassemble in 60 minutes today. Ortmayer notes that 39 of the 45 players who finished the season on San Diego’s 1989 roster were his products.

After being fired, Ortmayer came back to the Raiders and coaxed a few Chargers up the freeway with him: wide receiver Jamie Holland, running back Napoleon McCallum, tight end Andy Parker, tackle James FitzPatrick, defensive tackle Mike Charles and cornerback Elvis Patterson.

Ortmayer won’t allow emotions to stand in the way of Raider success. He built the present Chargers, for better or worse, but now hopes they lose every game.

“I know this is hard to believe,” he said. “But you get caught up so much with the emotions of winning a division title that you can’t afford to root for other teams in your division, even if you have friends there. You can’t. It’s too competitive on a day-to-day basis. Yet, individually, there’s a lot of people there I’d like to see succeed.”

Ortmayer’s stay in San Diego was controversial from the beginning. Remember, he left the Raiders to take over operations of a divisional rival, raising the usual suspicions that anyone who once worked for Al Davis never really works against him.

Those fears were confirmed in some minds after Ortmayer’s role in a major three-team trade that (1) landed the Raiders quarterback Jay Schroeder, (2) sent the Washington Redskins a Pro Bowl left tackle, Jim Lachey, and (3) gave the Chargers lineman John Clay, now out of the league, and later, McCallum, who has since returned to the Raiders.

Ortmayer heard the whispers, that he was a Raider masquerading as a Charger. He was always “Ort the Raider” to some San Diego loyalists. As in most rivalries involving the Raiders, paranoia rules.

Ortmayer will try to block out the past and concentrate on what promises to be a game that would have been interesting without the added dimension of Bo Jackson, who is expected to make his 1990 debut.

The Chargers, Ortmayer can tell you, are well stocked with defensive talent. They possess a punishing ground game, led by Marion Butts, and have a true star in receiver Anthony Miller. Yet on the road to 2-4, they’ve looked awful (two weeks ago against Pittsburgh) and brilliant (last week against the New York Jets with their most lopsided victory in 10 years, 39-3).

Quarterback Billy Joe Tolliver said the Chargers have to find a happy medium. “You have to play at a consistently high level every week that you go out,” he said. “A lot of it comes from experience. But you can overcome some of those things if you go out with enthusiasm. That’s what we’re going to try to do.”

Into this mix the Raiders will throw Jackson. Coach Art Shell isn’t saying how Jackson might be used today, but Jackson is expected to take Greg Bell’s spot in the second-quarter tailback rotation.

Shell said he’s looking for more out of Jackson this season.

“I want him to become more involved in the passing game,” Shell said. “I think that’s important. I don’t want it to be a one-dimensional thing, that when Bo’s in the game, then Bo Jackson’s going to run. Because he’s a pretty good receiver.”

Other than that, this game is merely another meeting between mutual friends and enemies and one former general manager who returns to the scene of the firing.

“Resentment has never been the right word,” Ortmayer said of his dismissal. “Disappointment is certainly a much better word. Disappointment that we weren’t allowed to complete the job we started.”

Raider Notes

The Raiders lead the series in San Diego, 17-10-1. . . . Charger running back Marion Butts is the AFC’s second-leading rusher with 505 yards in 105 carries, an average of 4.8 yards a carry. . . . Raider quarterback Jay Schroeder continues to lead the AFC in passing with a rating of 101.1. No other AFC quarterback has a rating as high as 90.

If running back Bo Jackson plays in all of the Raiders’ remaining 10 games this season, he will earn $140,000 per game. . . . Billy Joe Tolliver, San Diego’s second-year quarterback, on the Raider-Charger rivalry: “You don’t have to be here very long to understand the importance of the game. We’ve got two guys on this team that between them have 35 years playing experience, that’s (assistant coaches) Ed White and Charlie Joiner. So they can tell us all we need to know.”

Raider receiver Mervyn Fernandez leads the AFC with 522 yards in 28 catches. He and teammate Willie Gault are averaging 18.6 yards a reception. . . . The Raider and Charger defenses have 20 sacks each through six games, second in the AFC to Kansas City’s 24.