NHL free agency has opened with a flurry of moves.

Defenseman Matt Niskanen cashed in on his free agency, signing a seven-year, $40.25 million contract with the Washington Capitals.

The Capitals, trying to support superstar Alex Ovechkin with more talent, also signed defenseman Brooks Orpik to a $27.5 million, five-year deal.

Colorado veteran Paul Stastny got a $28 million, four-year contract from the St. Louis Blues.

Thomas Vanek and Ryan Miller were also on the move hours after the market opened Tuesday. The Minnesota Wild signed Vanek, a forward, to a $19.5 million, three-year deal. The Vancouver Canucks gave Miller a three-year deal worth $18 million.

More than 10 teams, including the Buffalo Sabres, handed out contracts worth more than $4 million a season on Day 1 of free agency.