WASHINGTON, D.C. -- It's no secret pitching is the biggest concern for the Nationals this season. It's the reason a lot of experts aren't expecting them to contend in the National League East.

Monday afternoon was an example of that concern. Right-hander John Patterson was hit hard, and the Nationals lost their first game of the season, 9-2, to the Marlins at Robert F. Kennedy Stadium.

It was Manny Acta's debut as the Nationals' manager, and he saw Patterson struggle throughout his time on the mound. Patterson lasted 3 2/3 innings and gave up six runs on seven hits. He threw 80 pitches; 46 of them were strikes.

It was Patterson's first Major League game since July 9. Patterson, who missed most of last season because of a pinched nerve in his forearm, acknowledged he was nervous before the game but said that had nothing to do with his poor outing.

Patterson knew from the time he had his bullpen session before the game something was wrong. He noticed he didn't have any zip to his fastball, and it carried over into the game. Patterson even hinted he may have had a dead arm. His fastball was clocked in the high 80s. It's usually in the low 90s.

During the game, Patterson had a tough time throwing his breaking balls for strikes, so he had no choice but to throw his fastball. Patterson had no answers for Marlins third baseman Miguel Cabrera and shortstop Hanley Ramirez. Cabrera drove in four runs, including a two-run home run in the fourth, which knocked Patterson out of the game. Ramirez had four hits with four runs scored.

"I didn't have any life on my fastball today, and I think that affected my slider and my curveball. I had a good changeup today. I didn't get a lot of opportunities to use it," Patterson said. "I don't know why I didn't have life on my fastball. I felt pretty good. Today [the arm] was just dead. I fought it. I tried to get the ball to jump and get a little life on it. It just wasn't there."

Patterson doesn't have an answer as to why his arm went dead. There is one theory, that he didn't throw enough during Spring Training. There was a time during the exhibition season where he didn't pitch for 10 days because of the March 13 off-day.

"I don't know [if that had anything to do with it]. I felt pretty good during Spring Training," Patterson said. "My velocity was up to 93 (mphj). Today, I don't even think I broke 90. It's just one of those days. It's just unfortunate that it was Opening Day."

Relievers Levale Speigner and Micah Bowie didn't fare any better, as they combined to give up three runs.

Florida starter Dontrelle Willis was solid, giving up two runs (one earned) in six innings. Brian Schneider drove in the first run with a sacrifice fly in the fourth inning, while Dmitri Young doubled home Ryan Zimmerman two innings later.

The Nationals had a chance to make it a game in the sixth inning after the Young double. Washington had runners on second and third and no outs. However, the next three hitters were left-handed, and Willis managed to get out of the inning. Schneider popped up to Ramirez at third, Ryan Church popped up to first baseman Mike Jacobs in foul territory and Chris Snelling lined out to Willis to end the inning.

"It was really frustrating. You want to drive the runs in there and do the job," Schneider said. "We had three lefties come up against him. It just seemed like when I had my at-bat, Dontrelle was throwing up to 93. He started getting that velocity up there. Dontrelle is a big-time pitcher. When he faces adversity, he seems to pick up his game a little more."

Acta's first day during the regular season didn't go as planned, but he saw a silver lining. His family saw him manage his first big-league game and he liked that there was a good crowd at the stadium.

"It was a beautiful day for Opening Day. Beautiful crowd. It's a great day," Acta said. "Somebody has to win, somebody has to lose. I lost today, but it was still a beautiful day. It was a special moment for my family."