Arnott, who is an unrestricted free agent at the end of this season, has 13 goals and 24 points for the Devils. He becomes only the second player on Washington's roster who has won the Stanley Cup, joining right wing Mike Knuble. The Capitals have been playing rookies Marcus Johansson and Mathieu Perreault as their second- and third-line centers for much of this season.
The 36-year-old Arnott was a key member of the Devils when they captured the Stanley Cup in 2000. He had 8 goals and 20 points in 23 postseason games that season and has 66 points in 106 career playoff contests.
Steckel has 5 goals and 11 points in 57 games for the Capitals this season as primarily the team's fourth-line center. He is one of the top faceoff specialists in the League (currently first at 63.7 percent) and has been a key member of Washington's penalty-killing unit.
The 28-year-old Steckel was a first-round pick by Los Angeles but never signed after four years at Ohio State, joining the Capitals as a free agent shortly after Bruce Boudreau became the coach of Washington's AHL affiliate in Hershey. He has two years left on his contract at $1.1 million per season.
Washington traded its 2010 and 2011 second-round picks at the deadline last year for Carolina defenseman Joe Corvo and Minnesota center Eric Belanger.