LAKE FOREST, Ill. -- Several mock drafts predicting the first round of next week's NFL draft project the Chicago Bears to select Pittsburgh defensive tackle Aaron Donald with the No. 14 pick.

Pump the brakes, says Chicago general manager Phil Emery, who indicated Tuesday that he doesn't expect Donald to be available once the Bears hit the clock at No. 14.

"Usually doesn't happen that way, does it?" Emery said, laughing, after being told of the many mock drafts projecting Donald to the Bears. "So I wouldn't count on that one. He's a very good player. When the dust is settled, usually teams understand who the top 10 players in the draft are. Then you'll see as the draft gets closer, the mocks get a little finer just because they're talking to people in the league, and everybody finally has kind of agreed on who the top 10 or 12 players in the league [are]. You'll see all those players, all of the sudden some of them are leaping from 18, 19, 20 … you'll start to see them at 10. [It's] because they have talked to enough people and people are saying, 'That's a really good player. That's a dynamic player. That's a difference maker.' And all of the sudden some of these folks that have been back there on mock drafts hanging back at 18 to 25 are all of the sudden in the top 12. They didn't rise. It's just that universal knowledge is being gained on who the top players in the draft are. So that's always an interesting dynamic to look at."

Certainly, it is. For the folks interested in trying to narrow down Chicago's potential selection at No. 14, Emery offered tips for how his team puts together its own mock draft every year. Emery said the club has narrowed its list of potential first-round selections to six players.

He'd be "happy" if two of those players remained on the board when the Bears picked, and "ecstatic if three of the six" were available.

"What we look at, not so much as mock drafts, we look at historical values of players at positions selected per round. We have our own mock draft in which we fill in from those historical values," Emery explained. "[For example] defensive linemen, say it's basically three players at defensive line that are normally taken in the first round. So you figure out, historically for this draft over a five- or a 10-year average, let's say the number is four. There have been four defensive linemen taken in every first round. So you figure out those four that are most probable, and you place them in the first round. Then you figure out what's the value for the second round. You build your mock that way and say, 'historically, this is what it should look like.' Then you have to kind of say for this draft, it's really [heavy on] offensive players. So we're gonna probably push one or two players at those positions out because there are going to be better offensive players.

"At the end of the day, you're going to select players that have the value for that pick. So you're going to push a few up. You just keep massaging that. We change it as the draft goes on. We take off the players that have been picked. We don't push them up. We still keep them at the value level that we had them in terms of round sequence. But it gives you a pretty good idea of who is gonna be available. You know what it's really valuable in is when you're discussing trade opportunities. You start looking at what's left on the board, historically what should be left, what those players are, what grades you have on them and the mock helps fine tune that for you. It's a tool."

It's obvious the Bears have put it to use in narrowing down the field of potential targets in the first round. Entering the draft, Chicago needs help mainly on the defensive side of the ball on all three levels. Given the club's heavy investments along the defensive line in free agency, it would make sense for the Bears to use their first-round pick on a safety, cornerback or linebacker.

But Emery considers the strength of the draft "in terms of depth, value and quality" to be offensive players. That's why the Bears -- despite needs on defense -- remain open to adding an offensive player at No. 14.

"There are good defensive players in this draft, and when it's our turn to pick, it's 'Does the player that we're [oriented] towards in terms of our need or wants, does his value match up with that pick?' That's the determination of taking any player," Emery said. "You want the player's perceived ability to match up with the level of the draft that he should be taken at. If there's a better player at another position either side of the ball, we're gonna take the best player that can help us win now. That's the most important thing."