Jeffries played for the Knicks from 2006 to 2010, but was traded to the Houston Rockets in 2010 as part of the deal that sent Tracy McGrady to New York. In February of 2011, the Rockets bought out Jeffries' contract and he decided to re-sign with the Knicks. He played 24 games with the Knicks last season, averaging 2.0 points and 3.4 rebounds per game.
Mike D'Antoni has said he appreciates the effort Jeffries puts forth. Though Jeffries is not considered a good scorer, D'Antoni likes his commitment to defense and believes the Knicks are better off surrounding superstars Carmelo Anthony and Amare Stoudemire with defensive-minded players rather than pure scorers.