There is a silver lining for the Elis in the absence of their top returning runner, David Knox ’06. It’s six feet, 187 pounds, and at New Britain (Conn.) High School, it scored 39 touchdowns — last season.

The arrival of Mike McLeod ’09 on campus has come with almost Barbara Bush ’04-like fanfare and for good reason. The rookie tailback, last year’s New Haven Register Player of the Year, spurned offers of interest from Penn State and Notre Dame to stay near home — and the move could pay off.

Since Knox went down last week for a still undetermined period of time, McLeod has split first-team practice reps with Jordan Spence ’07 , an undersized all-purpose back who ranked third on the team with 17 receptions a year ago.

Though the preternatural McLeod has shown flashes of future success, running backs coach Larry Ciotti gave Spence, who was solid in Yale’s intrasquad scrimmage last week, the slight lead heading into Saturday’s home scrimmage with Princeton.

“I’d say Jordan is ahead of Mike because of his experience,” he said. “It’s his third year with us and he’s very skilled at pass blocking. You have to be able to protect the quarterback. There are so many blitzes that you have to recognize. It takes time to learn, though McLeod is picking up on it pretty quickly.”

Another key is excelling in Yale’s zone-blocking schemes, which requires not only great vision but also the shiftiness that McLeod has shown in his ability to cut back a run against the grain to exploit an over-pursuing defense.

Still, a platoon in the backfield is always an option.

“In the good years we’ve had, we’ve always had two tailbacks splitting time,” Ciotti said, adding that Tyler Wells ’06 will also play. “It keeps them both fresh.”

Regardless of who is carrying the ball, the Yale ground game will face a sturdy Princeton defense, led by all-Ivy three-way star Jay McCareins, a natural defensive back whose brother Justin is a starting receiver for the Jets.

Rob Carr ’05 ran wild on Princeton last November, racking up 160 yards on 32 carries, but the improved and experienced Tigers defense should curtail Saturday’s totals and just might deliver McLeod his rite of passage.

“So far I’ve had no real shock,” McLeod said about the adjustment to the college game. “That hit that everybody says you get when you get to college? I haven’t taken that yet. It’s pretty similar to high school, only faster.”

When McLeod does find daylight, expect fireworks.

“He’s a slasher but with moves and speed,” Ciotti said. “Normally it would be a concern playing a 187-pound freshman tailback, but he plays a lot bigger. He has explosiveness and he’s tenacious.”

Coupled with Wally Pipp-rendering talent, a little tenacity might make McLeod the answer to the Bulldogs’ most maddening offseason question: Rashad Bartholomew ’01 , Carr ’05, then who?