(My Sportsbook) - Scott Olsen's first regular-season start with his new team will come against his former one, as the new Washington Nationals left-hander will take the mound for tonight's middle test of a three-game series with the Florida Marlins from Dolphin Stadium.

Olsen was drafted by the Marlins out of an Illinois high school in 2002 and broke into the majors with the club three years later. He spent the past three seasons as a mainstay in the Florida rotation and compiled a 31-37 record with a 4.63 earned run average during his tenure with the team, including an 8-11 mark and a 4.20 ERA in 2008.

The cost-conscious Marlins traded the arbitration-eligible pitcher, along with outfielder Josh Willingham, to the Nationals in November in exchange for infielder Emilio Bonifacio and a pair of minor-leaguers.

Bonifacio was one of Florida's heroes in Monday's 12-6 Opening Day triumph over the Nationals, as the speedy third baseman went 4-for-5 with a two-run inside-the-park homer in his Marlins debut. He also scored four times and stole three bases on the afternoon.

Hanley Ramirez belted a grand slam in the sixth inning and knocked in five runs overall for Florida, which also received home runs from Jorge Cantu and Jeremy Hermida. Cantu finished 2-for-4 with three RBI.

Ricky Nolasco was the beneficiary of the Marlins' offensive outburst, picking up the victory despite allowing five runs (4 earned) over six innings.

Adam Dunn, Washington's prized free-agent signing during the offseason, slugged a three-run homer and ended with two hits and four RBI in his first game as a National.

Washington starter John Lannan had a forgettable first Opening Day outing, as the young lefty was rocked for six runs and six hits before being pulled after three innings.

The Marlins picked up right where they left off against the Nationals in 2008. Florida won 14 of the 17 meetings between the divisional foes last season, including seven of the nine games played in Miami. Washington is just 8-20 at Dolphin Stadium since the start of the 2006 season.

Florida's Josh Johnson will oppose Olsen tonight and will be hoping to build on a very successful ending to his 2008 campaign.

After sitting out the majority of 2007 and the first three months of last season while recovering from Tommy John surgery, Johnson made an impressive comeback from the career-threatening injury. The talented right-hander posted a 7-1 record and a 3.61 ERA in 14 starts after returning to the mound, while notching 77 strikeouts over 87 1/3 innings of work.

Included in that string of outings were a pair of September victories over the Nationals in which Johnson surrendered just four runs over a combined 12 innings. The 25-year-old is 3-0 with a 3.12 ERA in five lifetime appearances (4 starts) versus Washington.