OXNARD, Calif. – To play tight end for the Cowboys, a player has to be smart and versatile.

Coaches like to say it’s the most difficult position to learn behind quarterback because you have to learn three different spots: on the line, in the slot and also fullback.

Jason Witten has mastered the spot with seven Pro Bowl appearances. John Phillips is more versatile than the man he is succeeding, Martellus Bennett, whose strength was as a blocker on the line of scrimmage.

But if the Cowboys ask their tight ends to play some fullback, can’t they ask their fullbacks Lawrence Vickers and Shaun Chapas to play some tight end?

Not really according to Jason Garrett.

“It’s a challenging thing for a fullback to go play on the line of scrimmage in the National Football League,” Garrett said. “We talk about the Y tight ed, the F tight end or the F fullback, it’s a rare guy who can do all three of those things. Being big and long is really important to play on the line of scrimmage in the National Football League. The guy you’re playing against is DeMarcus Ware, Michael Strahan, (Jason) Pierre-Paul. It’s all these kinds of big, long-armed defensive end players. If you don’t have the length and the height to play against those guys, they’re going to throw you around. You can be strong and you can be technically sound and all those things, but you can’t handle one-on-one battles. That’s the challenge for those guys to do that if you don’t have the physical traits to do that.”

Vickers is 6-feet, 250 pounds. Chapas is 6-2, 244 pounds.

At 6-3, Harry Flaherty is the shortest tight end. At 249 pounds, rookie James Hanna is the lightest.