WASHINGTON – No brawls, beanballs or even brushbacks yesterday between the Nationals and Mets.

No sellout and no bouncing stands, either, at Washington’s home opener, which was much more low key in almost every way than last season, when big league baseball returned after a 34-year absence to plenty of fanfare.

The announced crowd of 40,530 – more than 5,000 shy of capacity – didn’t have much reason to root, root, root for the home team. Rookie Brian Bannister shut down Washington’s struggling offense again for his first major league victory, and Carlos Beltran homered off the facing of the upper deck, leading the Mets past the Nationals 7-1.

“This is a team that is built to win,” said Bannister, whose father, Floyd, pitched in the majors. “I knew my role was to come in here and to lay low, to just eat up innings, to pitch any game they needed me to pitch, and to just give this team a chance to win every time. It wasn’t to come in here and take over the show.”

But he did precisely that yesterday, giving up three hits without a walk over seven innings. The lone run he allowed was on Alfonso Soriano’s homer in the seventh; last week in New York, the righthander held the Nationals hitless for 5 1/3 innings in his big league debut.

During that series at Shea Stadium, seven batters were hit – six by Mets pitchers – and a near-fight ensued. Nationals right-hander Felix Rodriguez and manager Frank Robinson were suspended by the league; before yesterday’s game, Robinson said, both managers were told umpires would watch all season for any sign of trouble when the NL East rivals meet.

Players played down the possible tension before the game, though Bannister (1-0) acknowledged afterward it was on his mind.

“At the beginning of the game, I was a little timid throwing inside,” he said. “Especially with Soriano, we did pitch away. As I got more comfortable, we started going back in.”

More interesting, perhaps, will be today, when Pedro Martinez starts. He hit three Nationals with pitches last week, including Jose Guillen twice. Since that game, Guillen is 3-for-18, 0-for-4 yesterday, and his struggles are emblematic of an offense that has totaled eight runs in three games, all losses.

While Bannister was in control throughout, Nationals starter Ramon Ortiz (0-2) found himself in trouble repeatedly, giving up four runs and eight hits in six innings. The Mets out hit Washington 12-3, and even Bannister got his first major league hit – two, actually, a single and a double.

Ortiz “gave up the first two [runs], and it’s almost like we’re out of the ballgame, the way our offense is going,” Robinson said.

Aaron Heilman and Billy Wagner each threw a hitless inning in relief for the Mets, which improved to 5-1. Wagner walked three and loaded the bases in the ninth, but struck out rookie Ryan Zimmerman to escape.

The Nationals’ first home game of their second season since leaving Montreal was definitely diminished. There were large patches of empty seats Tuesday when Vice President Cheney emerged to mainly boos and scattered applause for the ceremonial first pitch.

Mets third baseman David Wright has at least one RBI in each of the Mets’ first six games, a club record to start a season.