But Harbaugh said other teams will be following suit, saying there could be as many 120 or 130 players released to get teams under the cap. That could put as many as 500 free agents onto the market.
"I think it's going to be unpredictable," Harbaugh said as the doors opened at Ravens headquarters Tuesday. "I think you always have to look to make your team better. There's probably going to be an opportunity in terms of the market being flooded with players that has never happened in the history of the National Football League and probably won't happen again the next 10 years. So we've got to do everything we can to take advantage of it and improve our team, and we're going to need a little space to do that."
The release of those four veteran players created $18.6 million in cap room.
"It's just the reality of the salary cap," Harbaugh said. "It's the situation we're in right now. In going forward, we've got to make the best team we can. That's not that we're ruling anything out, either. I think in this climate, anything is possible."
Harbaugh didn't cut ties altogether with Heap, Mason, Gregg or McGahee back.
"You may have an opportunity to bring some of those guys back. You may not," he said. "It just depends on how it shakes out the next couple of days."
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