The Cowboys placed the defensive tackle on injured reserve on Tuesday with a bone bruise to his right knee, and signed veteran linebacker James Anderson. Melton, who signed a one-year deal with a three-year option with the Cowboys as a free agent, was injured in the season finale against the Washington Redskins. He finished the year with five sacks and 10 tackles.
Melton had nine games in which the coaches did not credit him with a tackle.
If the Cowboys pick up his option, Melton would be guaranteed $9 million in 2015.
"I can't think about that," said Melton before the club announced the move to IR. "I love it here in Dallas, love the fans, love everything. So right now we're just working for this playoff push and take it one day at a time."
Melton was looking at a prolonged absence and the Cowboys felt the need for a roster spot. Anderson played in seven games with the Tennessee Titans before signing with the Atlanta Falcons on Nov. 20. He did not play in a game before his release on Dec. 24. In 2013 he started 16 games for the Chicago Bears and had 102 tackles and a career-high four sacks.
Melton signed with the Cowboys after missing all but three games last year with the Bears because of a torn ACL in his left knee. He had five sacks in the first nine games but did not get to the quarterback in the final seven.
"Personally I didn't get it exactly where I wanted to get it," Melton said. "It was rough coming back and I think one of the major factors was I had to get back into playing shape. But it is what it is ... a lot of people told me about it's going to take one step to actually feel confident in it and there's another step where you've got to be able to go play and breathe and be able to run on it."