It’s tough duty being a relief pitcher in the major leagues. You can be a hero one day, a bum the next. You’re only as good as your last appearance.

Seth Lugo was reminded of that Sunday night at Citi Field where his streak of 15 scoreless innings ended when he gave up a crucial run in the top of the ninth inning that proved to be enough for the Dodgers to escape with a 3-2 come-from-behind win.

It had to happen at some point. Lugo had been brilliant of late. He hadn’t allowed a run since Aug. 17 and had retired the Dodgers in order Saturday night to earn the win in the Mets 3-0 victory.

But after getting the final out of the eighth inning Sunday night, Lugo surrendered a run in the ninth when Kiké Hernandez hit a double off the wall with one out before Jedd Gyorko slashed a two-out hit to drive in the game-winning run.

Lugo took the loss, but don’t blame Lugo for the dire situation the Mets find themselves in four games out of the final wild-card spot with 13 games to play. He has been too good for that. An argument can be made the right-hander might be the most important contributor to keeping the Mets in the postseason race. Entering the game, he was 1-1 with five saves and a 1.86 ERA since the All-Star break and has emerged as Mickey Callaway’s go-to guy after high-priced closer Edwin Diaz lost his confidence and became unreliable.

But as his stock as a reliever continues to rise, Lugo made it clear he still thinks of himself as a starter.

“All my personal goals are starter-based,” Lugo said after Saturday’s game. “I’d like to win 20 games. I’ve still never had a nine-inning complete game. I had a seven-inning one in the minors in a doubleheader. All my goals are more starter-based.”

It seemed an odd time for Lugo to be reminding everybody he’d rather be doing something else than what he’s actually doing to help his team. His comments came after being questioned why he pitched out of a full wind-up Saturday night and his answer was something like, “I’m a starter. Gotta keep my wind-up.”

Though the timing might be odd, you can’t blame Lugo for taking the opportunity to remind the Mets that he’s a starter at heart. Taken in the 34th round of the 2011 draft, he completed his long-shot journey to the big leagues in 2016 where he made five starts and two relief appearances.

Lugo was in the starting rotation in 2017 where he was 7-5 with a 4.67 ERA, but all but five of his 54 appearances in 2018 came as a reliever. All 53 of his appearances this season have come as a reliever where he has emerged as one of the team’s most valuable players.

“He can be a multiple-inning reliever,” Callaway said. “He can be just a closer. He can be a starter. I think he could fulfill anything you want and whatever the team needs.”

Callaway said he doesn’t mind Lugo lobbying to be a starter even in the midst of a pennant race. With Sunday night’s loss, the Mets are four games behind the Cubs for the second wild-card spot.

“We understand his feelings,” Callaway said. “He views himself as a starter someday and he probably will be at some point. We feel like he could start. But at this moment our best team is with him in the bullpen. That could change or that could stay the same way.”

Money might also be a motivator. The top-10 highest-paid starters earn anywhere from $25 million to $34 million a year, while the top 10 closers earned from $6.5 million to $17 million. Lugo is making $591,875 on a one-year contract this season.

Maybe he just wants to escape being a winner one night and a loser the next.

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