The Washington Nationals dealt Noah Syndergaard his first loss in more than a month, an 11-4 victory over the Mets on Monday night in the opener of a three-game series between the division rivals.
Washington starter Joe Ross (7-4) gave up four early runs then retired 11 of the last 12 batters he faced.
The Nationals increased their lead over idle Miami to 3 1/2 games in the NL East, while the Mets are four games back. The Nationals stole six bases, matching their most since the franchise moved to Washington in 2005.
Five steals came against Syndergaard (8-3), who had won six consecutive decisions and had not lost since May 6. He lasted only three innings, surrendering season-highs in runs (5) and walks (3).
Ross struggled as New York built a 4-0 lead. Manager Dusty Baker visited the mound after the first four hitters reached in the third inning, and Ross got the next nine batters out and completed six innings.
The Nationals' offense erased the deficit in the third inning, scoring five times while batting around against Syndergaard. They would add five runs over the next two innings against reliever Sean Gilmartin.
Ben Revere had four hits and three steals and Anthony Rendon had three RBIs for Washington, which had its largest scoring output since an 11-4 victory at the Chicago White Sox on June 8.
Washington recalled RHP Rafael Martin, who was 1-3 with a 4.40 ERA and 14 saves at Triple-A Syracuse. Martin pitched a scoreless ninth Monday.
Mets: LHP Steven Matz might not make his scheduled start Wednesday because of elbow discomfort, manager Terry Collins said. Matz underwent an MRI on Monday in New York and will be re-evaluated Tuesday.
Nationals: RHP Stephen Strasburg underwent an MRI on Monday morning, Baker said. Strasburg was scratched from his last two starts with an upper back strain and was placed on the DL on Sunday.
Mets: Matt Harvey, who owns a 2.25 ERA in five starts since absorbing consecutive losses to Washington, faces the Nationals for the third time this season.
Nationals: Top prospect Lucas Giolito will make his major league debut Tuesday. Giolito, the No. 16 pick in the 2012 draft, is 5-3 with a 3.17 ERA and 72 strikeouts in 71 innings at Double-A Harrisburg this season.