As was feared on Sunday, an MRI confirmed that he tore his ACL.
He is expected to undergo surgery next week.
This is a disappointing end to a season in which Ta'amu was a bright spot on the team. Picked up as a waiver claim in the preseason from the Pittsburgh Steelers, he split time all season in base defensive packages with Dan Williams at nose tackle and sometimes, in jumbo sets, play alongside Williams. Between both players, they performed very well and were a big part of why the defense was the league's best against the run.
He will have months of recovery and rehabilitation.
What is even worse than his injury is the timing. Ta'amu is not under contract for next season, which means Arizona must decide whether to retain him, which becomes a bigger question because he will likely miss a chunk of the 2014 season.
However, he is an exclusive rights free agent, which means the team can offer him a basic tender that amounts to being about the league minimum between $400,000 and $500,000. It will cost very little to keep him around. He can begin training camp and the season on the PUP list and then add him late in the season after he is ready.
Do I expect him to return? Definitely. At that low price, it is worth it to retain him, especially since he will be under team control next offseason as a restricted free agent. The potential production he will bring is likely worth having him back.