NHL: The quest for Lord Stanley's Cup continues as three more first-round playoff series start tonight. In the Eastern Conference, we've got Montreal at Boston (7 p.m. ET, Versus). It's the 33rd all-time postseason series between these teams, making it the most common playoff matchup in NHL history. At 7:30 p.m., Buffalo visits Philadelphia. The Sabres seek to knock off the defending Eastern Conference champs for their first playoff series win since the 2007 conference semifinals. In the Western Conference, Los Angeles visits San Jose (10 p.m.), marking the first playoff matchup between these two teams. It's the Sharks seventh-straight postseason appearance, the second-longest active streak in the NHL. For more on these matchups, we've got you covered here.

MLB: Here are a few of the games we're checking out on a busy MLB day. Thanks to a rainout, the Mets and Rockies will pay a good old-fashioned doubleheader starting at 12:10 p.m. at Citi Field. The Rockies are a red-hot 8-2 to start the season. ... The Rays seek their first win at Tropicana Field this year (0-5 at home) in the first of four against the Twins (Carl Pavano vs. James Shields, 6:40 p.m.). ... The Orioles and Yankees are tied atop the AL East for now. The winner of tonight's rain-shortened two-game set at Yankee Stadium takes sole position of first place (Jake Arrietta vs. Phil Hughes, 7:05 p.m.). ... Cliff Lee and the Phillies took to continue their domination of the Nationals (Lee vs. Jordan Zimmermann, 7:05 p.m.). ... L.A. and St. Louis play the first of four at Chavez Ravine in what should be an excellent pitchers' duel between Jaime Garcia and Hiroki Kuroda (10:10 p.m.).

NFL: Court-ordered mediation between the NFL and NFLPA begins today in Minneapolis. NFL commissioner Roger Goodell and several NFL owners are expected to be in attendance, including Clark Hunt (Chiefs), Robert Kraft (Patriots), Jerry Richardson (Panthers) and Art Rooney (Steelers).

Information from ESPN Stats & Information was used in this report.