Placing only the tender on Wallace would leave Pittsburgh open to being poached for its top wideout by teams willing to fork over a long-term contract and a first-round draft pick. One such club could be the division-rival Ravens, who draft 29th overall. The cap-strapped Steelers may see the monetary difference between the tender ($2.742 million) and tag ($9.6 million) as worth the risk.
For the tag, teams only have to pay a 1st (no longer a 3rd) to get the player, though the first team can match. And there had been questions if other teams would pay that cost.
If they are only going to tender Wallace, it is going to cost them more than the tag number. Some team is going to step up and pay 10mil/year -- 49ers, Broncos, Ravens, Pats x2 all have low first round picks and need at WR.