YESTERDAY Chip Kelly again spent a couple of minutes of his news conference responding to weekend rumors about a return to college coaching. This time the school was Texas. A few weeks ago it was the University of Southern California. As he did then, Kelly summarily dismissed it, saying, "I haven't spoken to anybody nor will I speak to anybody."

He is 14 games into a professional coaching career that, by contract, is supposed to last six seasons. And he has taken a team expected to pick high in next spring's draft to the brink of a playoff spot, Sunday's horrific effort against the Vikings not withstanding.

So why does his name keep coming up, someone asked.

"I don't know," he said. "I really don't know."

I do. It's because it looks like he's not having as much fun as he did in college. It's because the nuances and unforgiving nature of the pro game sometimes chew him up.

On Sunday, he challenged the play after the play he should have challenged. He went for it on fourth-and-18 inches from his own 24, a gamble he habitually got away with at Oregon. His out-of-the-box strategy to avoid Vikings rookie returner Cordarrelle Patterson put his refurbished defense - whose recent success was so intertwined with field position - on short fields literally all day long.

There's even an argument to be made that his team would already have a playoff spot locked up if not for the first-year coach's learning curve. He likely would have beaten San Diego in Week 2 with better clock management at the end of the game. It sure would have helped if he knew he could re-insert Michael Vick into that late drive by calling a timeout.

"That one was on me," he said at the time, and so was a quirky decision to go for a two-point conversion after the Eagles had cut into Kansas City's 10-0 lead in Week 3 - a decision that he defended.

"If you get a chance to steal a point here or there, in the long run, it can really benefit you," he said then. "That's always been our philosophy. Does it mean we're going to do it all the time? No, I think you pick and choose it."

There are good NFL coaches, and there are great NFL coaches and there are all the rest. There is no denying, especially now, that Andy Reid is a good coach, or that Marty Schottenheimer once was and you can go on and on. Good coaches are organized, evaluate talent well, are both students and teachers of the game. Their best days often fall from Monday to Saturday.

Great coaches are good coaches whose best day is often Sunday. They force you to play into their hands. They take away your favorite thing to do. They adjust, they improvise, they have all those little things that can cost you games covered and covered and covered again.

Once Bill Belichick was awful at deciding what and when to appeal. Now he excels at it. Great coaches win those little wars, treat their timeouts like chess pieces, not midgame snacks. More than anything, though, they think on their feet and they think fast, faster than the guy across the field thinks.

It's one of the attributes that made Kelly so attractive to Jeffrey Lurie and Howie Roseman post-Reid. His rapid-fire offense at Oregon was a striking contrast to the plodding pace seen here over the previous 14 seasons. And while that's been slowed with the change from Vick to Nick Foles, the Eagles' success since then might be the most exciting revelation about their new coach thus far.

Bum Phillips once said that Hall of Fame coach Don Shula "can take his'n and beat your'n and take your'n and beat his'n." It may be the best summarization of what makes a good coach great.

Kelly received due praise for adjusting the game plan in the snow against the Lions two Sundays ago. As simple as it looked, putting LeSean McCoy between the tackles instead of running him outside of them changed the face of that game in a microwave moment and provided a hint that Kelly may be more than just good at what he does.

But like the team he's coaching, that product is far from finished - something he readily admitted yesterday when I asked him, in light of his name coming up again for a college job, whether he felt part of the professional coaching realm yet.

"I've considered myself a pro coach eight times this year," he said.

"And six times I haven't."

On Twitter: @samdonnellon

Columns: ph.ly/Donnellon