The view into the abyss isn't particularly reassuring, not with a couple of unknowns like Lorenzo Booker and LeSean McCoy looking back at you.

The Eagles were bound to face life without Brian Westbrook eventually. That's just how it is in professional sports, especially this sport. Players know an injury could end their careers at any time - whether it's a sudden catastrophic blow or the slow erosion of their ability to run fast enough, push hard enough, or change direction suddenly enough.

Today's ankle surgery is only one reason to worry that Westbrook may not be Westbrook anymore. His earlier knee surgery is another. But perhaps the most alarming sign was the season that preceded this off-season of repair jobs.

In 2008, Westbrook was not nearly the explosive, game-changing player he had become over the previous four seasons. He just wasn't. The hope was that surgery would ease the swelling and pain in his knee and return him to form. That hope took a major hit with news that Westbrook now needs ankle surgery.

The issue isn't whether Westbrook can rehab from ankle surgery in three months - surely he can - but whether the accumulation of injuries will ever allow him to be the weapon he was from 2004 to 2007.

The Eagles have to proceed now as if he won't be.

By drafting McCoy in the second round - the highest Andy Reid has ever taken a running back - the Eagles signaled that they were preparing for life after Westbrook. But now you have to wonder if they're going to get caught short after all.

When Reid got here, Duce Staley was starting his third season. He sat his rookie year behind Ricky Watters and Charlie Garner. By 1999, Staley was an every-down back. By 2001, Staley was battling injuries and being supplemented in the offense by veteran pickup Dorsey Levens.

The Eagles drafted Westbrook in 2002. He was not the full-time starter until 2004. That wasn't because Westbrook wasn't fast or elusive or talented enough. It's because it takes that long for a running back to fully grasp this offense.

So expecting McCoy to be effective right away feels like wishful thinking.

"It's hard to talk about playing immediately if I don't know what I'm doing," the wide-eyed rookie said after hearing about Westbrook's latest surgery. "I'm a rookie, man. I've got to pay my dues as far as learning this offense."

McCoy said his "head is spinning," which is typical. He seems like a bright kid, and there's no reason to believe he won't get the hang of it. But if it took Staley and Westbrook time, chances are it will take McCoy time.

In some ways, it will actually be harder. Something Reid said the other day echoed into the abyss. He was asked about McCoy lining up at times as a wide receiver.

"That's part of our offense," Reid said. "That's become something we did with Brian, and we just kind of continued that as part of the offense now. We are expecting him to learn it. That is a base part of the offense, and we expect him to learn it."

In other words, the offense has evolved because of Westbrook's unique skill set. The job description for a running back has been rewritten. So McCoy and Booker don't just have to be good backs, they have to be good Westbrook-style backs. Either that or the whole offense has to be reconfigured.

"Nobody is going to come in here and take carries from Brian Westbrook," Booker said. "He's the career leader in yards from scrimmage in franchise history. That says everything. And in terms of this offense, and having a back that has to block, run and catch, there isn't a better back in the league that does all of that."

Booker sounds very confident in his ability to fill in, if necessary. It could be that he's precisely where Staley was in 1998 and where Westbrook was in 2003 - finished with his apprenticeship and prepared to step in. He didn't play much in 2008. Only Reid and his staff know whether that was a result of their strategy or Booker's performance.

"They had a plan that I wasn't aware of until later on in the year," Booker said. "They told me all during last year, in the future, you're going to be a big part of this football team."

The drafting of McCoy suggests the Eagles were looking for a new heir to the top running back job. Would they have done that if Booker was their guy? Or was the pick more about creating a new 1-2 combination to replace Westbrook and departed free agent Correll Buckhalter?

Either way, you suspect the plan was based on Westbrook being Westbrook in 2009, on the abyss being another year away.

Contact columnist Phil Sheridan at 215-854-2844 or psheridan@phillynews.com. Read his recent work at http://go.philly.com/philsheridan.