Forty yards can make or break you as a football player.

NIU football player A.J. Harris knows how true that is. When he and the rest of his teammates walk into the Convocation Center at 7 a.m. today, all their bodies will be tuned for one thing and one thing only – speed.

For underclassmen at the NIU Pro Day, speed is what counts.

“You have to run a good 40 time,” Harris said. “I mean, you have to take tests and stuff, but what matters is that you run well for the scouts.”

Harris will show up at 7 a.m. and take the necessary tests given to him by NFL scouts and his coaches. But once 8:30 a.m. rolls around, he knows it will be his time to show himself.

And that is what an ideal pro day is for, NIU football coach Joe Novak said. Though many seniors will get a chance to run in front of scouts at 10 a.m., today is a day for the rest of the team.

“Everybody on the team will run,” Novak said. “It’s a great thing because it gives [the NIU coaches] an idea of a player and also allow us to see if a player is making progress.”

One Huskie who won’t be testing his body in the 40-yard dash is senior receiver Dan Sheldon.

Sheldon was invited to the NFL combine in Indianapolis – along with fellow senior Josh Haldi – in late February, but during his workout he reinjured a collarbone injury he suffered during the Silicon Valley Football Classic.

Sheldon said his collarbone is still bruised and a little sore, so instead of trying to run this morning, he has rescheduled his workout for April 13.

“I did the important things at the combine,” Sheldon said. “I ran and caught passes. But postponing my run will allow me to get back to 100 percent.”

The rest won’t just allow him to heal up, but it will also give him a better idea about who is serious about picking up the receiver who was No. 31 in the nation last year with 936 receiving yards.