Livan Hernandez walks off the field at Nats Park and acknowledges the crowd. (Patrick Smith/Getty Images)

As Livan Hernandez ambled in from the bullpen early Sunday afternoon, the Nationals Park crowd stood and applauded. Hernandez lifted his cap in the air. The 29,671 fans in attendance knew what the day portended for Hernandez, and so did all of the Washington Nationals teammates who call him, simply, Livo.

“I was thinking, ‘There’s a chance this could be the last time Livo pitches in a Nationals uniform,’ ” Ian Desmond said. “For me, it’s a little bit sad.”

The man who ushered baseball back to Washington may have performed the final act of his Nationals tenure Sunday afternoon. In his last start of the season, a 6-3 loss to the New York Mets, Hernandez allowed six runs in 51 / 3 innings, leaving with the bases loaded in the sixth inning. He doffed his cap once more, maybe for the last time with the Nationals.

The Nationals want to make room for Stephen Strasburg, Tom Milone and the rest of a young pitching rotation as they play their final month. In order to do so, they sent Hernandez to the bench, where he will offer wisdom to young players and his opinion to coaches.

Hernandez has almost reached the end of his $1 million, one-year contract. He wants to return to the Nationals next year, as a long reliever if necessary, and has expressed his modest contract demands to General Manager Mike Rizzo. He is waiting for an answer.

“This city is a great city for sports,” Hernandez said. “You can see the Redskins, they got like 10 years sold out. This team is not far away from making the playoffs. I want to be part of that.

“I can’t answer that question. I can’t say something that’s not in my hands. I know what I want and I asked for something. I can’t do nothing. I got to wait and see what is the answer. It’s not in my hands. But what I’m asking is not too much. It’s not something that you go throw the bank down.”

The contract “negotiations” between Hernandez and the Nationals last season colors Hernandez’s feeling for how this year’s deal should be handled. At the end of August last year, he approached Rizzo in a hotel lobby, passed him a slip of paper with “$1 million” written on it and said, “I play for this.” The statistical Web site valued Hernandez’s contributions to the Nationals this year — he compiled a 4.47 ERA in 1751 / 3 innings — at roughly $9 million.

“You compare the level of the people who throw 200 innings a year, I think I’m the most cheap guy,” Hernandez said. “It’s more important that you feel happy. Everybody told me, ‘You can make more money.’ It’s not about the money. We’ve got all we need.”

As Hernandez prepared to move aside for youth, finality and uncertainty tinged Sunday. Afterward, two baseballs sat in his locker. One had been saved from Tuesday, when he threw the 50,000th pitch of his career. The other, from Sunday, had scrawled on it, “Last Pitch.”

“It’s tough,” 39-year-old catcher Ivan Rodriguez said. “I’ve been there before, and it’s tough.”

Hernandez retired the first six hitters he faced before the Mets struck for two runs in the third. His start unraveled in the sixth. After Lucas Duda hit a one-out, upper-deck home run to right-center field, Hernandez loaded the bases with three consecutive singles.

In the dugout, Manager Davey Johnson did not want to make the walk to the mound. “He’s probably the hardest hook I have,” Johnson said. But he knew he had to.

Hernandez slapped gloves with his infielders, pressed the baseball into Johnson’s hand and walked off the mound. The crowd stood and applauded. Hernandez removed his cap and looked around the stadium, waving it until he reached the dugout and, down the steps, disappeared.

“If it’s the last,” Hernandez said, “it’s the last.”

If they do not bring Hernandez back, the Nationals will be cutting ties with the man who threw both the first pitch in Nationals history and the first major league pitch in Washington, at RFK Stadium, in four decades. Pitching for the Nationals in at least parts of five of their seven seasons, he became the team’s all-time leader in wins (44), innings (8282 / 3) and strikeouts (476).

He is, of course, more than numbers, a wholly unique baseball character. Hernandez’s nonchalant bravado and carefree style have endeared him to fans, even after he became the target of a federal money laundering investigation this spring. Teammates have adored him and appreciated him.

“It’s not even here. It’s everywhere,” Desmond said. “Everybody loves him. He’s the same guy, every day. He never comes in in a bad mood. He’s just Livo. He brightens places up. Guys on other teams, people at hotels that we go to, everyone knows him. Everyone knows Livo and the style of person he is.”

Hernandez has an effect on his teammates “when you see somebody that happy all the time,” Nationals left-hander John Lannan said. “He’s getting shut down early, and he’s still as happy as can be. Of course, he’s probably upset. But at the same time, he’s enjoying life and being here.”

Desmond joined the franchise in 2004, drafted by the Montreal Expos. “When I was a kid, he was taking care of me,” Desmond said. “Now I’ve matured a little bit, and he’s still the same guy towards me. He’s been like a big brother to me ever since I was a kid. I’ve got a special place in my heart for him.”

Hernandez arrived at the Nationals’ clubhouse Sunday morning wearing white jeans and black leather designer sneakers — big league all the way. He went about his usual rubber-armed warm-up routine, which includes an 80-pitch session in the bullpen.

The second batter of the game, Justin Turner, dribbled a chopper up the middle. Hernandez took a few steps off the mound, casually stabbed at the ball with his red glove and tossed the ball to first base. Everything about his play said, “I guess if I have to field it I will.” But there was never any question about the result.

“He’s one of my dad’s favorite pitchers to watch,” Lannan said. “He makes it look so effortless and easy. No one does it like him.”