In four years, Eric Dickerson and Craig James have co-authored a remarkable Book of Numbers under the pen name of "DickerJames."

With the exception of eight games in their freshmen year, Dickerson and James have shuttled back and forth at the tailback position for Southern Methodist University. From an option offense behind quarterback Lance McIlhenney, they carried 1,560 times for 8,192 yards and 70 touchdowns.

In today's Cotton Bowl game against the University of Pittsburgh, DickerJames will be running together for the last time.

Dickerson, who finished third in this year's Heisman Trophy balloting behind Herschel Walker and John Elway, is a slashing runner who has averaged eight yards a carry this season and scored on runs of 80, 80, 79, 70 and 63 yards. Even while splitting playing time with James, this year Dickerson eclipsed Earl Campbell's career rushing record and averaged 147 yards per game.

James, in addition to joining Dickerson in the all-Southwest Conference backfield, also led the conference in punting with a 44.9 average. James' 96-yard touchdown catch against North Texas State this year tied for the longest play from scrimmage in SWC history.

Coach Bobby Collins, like his predecessor Ron Meyer, was able to wear down opposing defenses by resting one great runner while playing another.

The obvious questions, though, persisted. Questions of ego. Did it bother James that he wasn't playing more? Did the shuttle system cost Dickerson the Heisman Trophy?

One position, two men. That sort of situation is famous as much for the dissension it creates as for the results it produces. Look at the recent quarterbacking history of the Los Angeles Rams.

But if either Dickerson or James was frustrated, the feeling showed up neither in the press nor on the field. They answered the ego questions as patiently and graciously as Miss America contestants.

"It's about time for us to have our own identity," said a hoarse-throated Dickerson at a bowl-week press conference. "You always hear about the Pony Express. My freshman year I didn't deal with it very well."

James agreed: "Eric and I have become friends and we will be friends for the rest of our lives. Now, we're ready to go out and show what each of us can do on his own."

This is not bitterness surfacing, however. Dickerson said, "This is sad for me. This is the last time we'll play as a group. The four years went so fast. Once, I wanted it to get over. Now, I wish I could stop it."

Since their sophomore season, when the shuttle system backfield became the pattern for SMU, Dickerson and James have led the Mustangs to two SWC titles. This year they are 10-0-1. The one blot on the Mustangs' record is the 17-17 tie with Arkansas that closed the regular season.

Their opponents, the Pitt Panthers, are 9-2, having lost to Notre Dame, 31-16, and Penn State, 19-10.

Offensively, Pitt is led by Dan Marino, a quarterback many thought would make a better run at the Heisman than he did. Marino, a drop-back passer, is protected by two all-America offensive tackles, Jimbo Covert and Bill Fralic. Marino, no matter how much time he has, will be throwing against a strong SMU secondary, led by cornerback Russell Carter.

Pitt Coach Foge Fazio said the defensive team has spent about 90 percent of its practice time working against I-formation option running attacks.

"We had no success against Florida State's option," said Fazio. "We did have two weeks to prepare for it now. I hope that was enough."

It rained Friday and it may still be raining at game time New Year's Day, a factor that may give the running SMU team an edge over the passing Panther team. On the other hand, some observers feel Pitt has faced a tougher schedule.

It is no secret, even here in Dallas, that the Sugar Bowl game between Penn State and Georgia will, more than likely, decide the national title.

SMU Coach Collins, though, said, "I feel like we're playing for a national championship. If Georgia should lose, and we should win, we'd be the only unbeaten football team in the country."

Fazio ventured that there is one scenario for his twice-defeated Panthers to capture the top ranking: "If we win Saturday, and the Georgia-Penn State game is canceled, then we have a chance."