WASHINGTON — The appropriate nickname on the back of Hansel Robles’ players weekend jersey would have been “BB.”
Robles, the erratic Mets reliever, was at his worst Sunday night, flushing a lead in the sixth inning against the Nationals as he refused to throw a strike.
In all, he walked three straight batters and was charged for two runs, sinking the Mets in a 5-4 loss at Nationals Park in the nightcap of a doubleheader.
The Mets won the first game 6-5 with Amed Rosario hitting a go-ahead homer in the eighth inning.
After Robles walked in the tying run in the nightcap, Chasen Bradford entered and issued a walk to force home the go-ahead run. The Mets never recovered in the late innings and finished with a split in the four-game series.
“[Robles] is better than that,” manager Terry Collins said. “You can’t walk guys in the big leagues. You have got to go get them.”
Seth Lugo, in his first start off the disabled list, was removed after throwing 70 pitches. The right-hander lasted 3 2/3 innings and allowed two earned runs on four hits with five strikeouts.
Brandon Nimmo’s first homer of the season, a two-run blast in the sixth, gave the Mets a 3-2 lead before Robles’ implosion.
Rosario cleared the center-field fence in the eighth inning of the first game against Joe Blanton for the Mets’ third homer of the afternoon.
Two weeks ago, Rosario hit a go-ahead homer in the ninth inning in Philadelphia that led the Mets to victory. The power display comes after a minor league career in which Rosario hit only 17 homers in 1,775 at-bats.
“I came from a league where I wasn’t seeing pitches come at me this fast,” Rosario said. “But as I have adjusted, I feel that I am doing better.”
And defensively, Rosario — as advertised — has shined.
“Our guys keep coming in with our defensive analysis, and he has moved us up immensely, just with his play at shortstop,” Collins said. “He has played great there.”
AJ Ramos recorded the final six outs for the save. The game ended with Edwin Jackson thrown out at the plate by Asdrubal Cabrera attempting to score on Daniel Murphy’s double.
Lefty Tommy Milone gave the Mets a solid, albeit abbreviated, performance by allowing one run on six hits over 4 1/3 innings before his bullpen flushed the lead by allowing four runs over the seventh and eighth innings.
Cabrera’s three-run homer in the first inning gave the Mets a fast lead. Wilmer Flores hit a two-run blast in the third that extended the Mets’ lead to 5-0.
Rafael Montero allowed two earned runs in a relief appearance in the sixth inning, but is still on track to make his next start, according to Collins. Montero is scheduled to pitch on Wednesday in Cincinnati.
“This was a side session,” Collins said. “I just thought in the middle of the game there if he could get us one or two innings we would take it and try to save somebody.”
Flores’ homer was his 17th of the season, a career high. Flores hit 16 homers in both 2015 and ’16.