Spencer needs a big season in 2012 to warrant a new deal. (Getty Images)

The last franchise tag applied before the March 5 deadline was the one given to Cowboys linebacker Anthony Spencer: Dallas snuck their tender in about an hour before the deadline.

Clearly, they were unsure about whether or not to guarantee the frustrating linebacker $8.8 million in 2012. Which is why it's not surprising to hear his agent say that Spencer won't be getting a new deal before the 4 p.m. ET deadline to extend franchise-tag players on Monday.

"We will start the season with his current contract," Spencer's agent, Jordan Woy, told ESPN's Todd Archer. "We will see what happens during the season. I'm sure we will have a discussion before the season ends."

There might be discussions, but there won't be a new deal: once Monday afternoon runs around, teams cannot sign franchise-tagged players to new deals until after the 2012 regular season ends.

Spencer would need a breakout season to warrant the Cowboys investing any more money in what's looking like a sunk cost. The Cowboys linebacker, taken with the 26th overall pick in the 2007 NFL Draft, has just 21.5 sacks in five years, despite playing across from DeMarcus Ware in the Dallas defense.

The Cowboys could also franchise tag Spencer again in 2013, which would result in paying the linebacker $10.6 million guaranteed ... and seriously wasting Dallas' already reduced cap space for the second year in a row.

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