A two-run blast by Danny Espinosa seals the victory for Washington on Sunday afternoon. (Nam Y. Huh/AP)

About 50 minutes before the first pitch Sunday afternoon, General Manager Mike Rizzo stood in the Washington Nationals’ clubhouse and told the team Davey Johnson would be their manager Monday . Then he turned to the man next to him, John McLaren, and thanked him for enduring an awkward three-day managerial tenure, maybe the last three days he will ever wear a major league uniform. The players’ applause could be heard in the corridor outside.

In the Nationals’ final game before Johnson becomes their manager, they provided McLaren a parting, 2-1 victory over the Chicago White Sox at U.S. Cellular Field, their 13th win in 15 games on McLaren’s last day in the Nationals’ dugout. Danny Espinosa crushed a two-run homer in the seventh inning and Livan Hernandez gave up one run in 6 2 / 3 innings, yielding eight hits and striking out nine — his most since September 2004 — in 123 pitches.

Afterward, each player hugged McLaren outside the dugout on his walk off the field. McLaren had helmed the Nationals for three games after Jim Riggleman’s stunning resignation, his loyalty lying with Riggleman, his heart with the players.

“The John McLaren era is over,” McLaren said. “Is three games an era?”

Whatever it was, McLaren’s time ended with the Nationals having won five straight series, the latest halting Chicago’s 18-series interleague winning streak. White Sox starter Phil Humber held the Nationals without a hit until Jerry Hairston led off the sixth inning with a line-drive single to center field. The Nationals, while winning 18 of 25, have proved they don’t need many runs to win. Sunday, they won by a 2-1 score for the sixth time in June.

“This is what we do here,” Hernandez said. “We play hard every inning, we try to score some runs, we play good defense behind, we pitch good, the bullpen is amazing. That’s it.”

Johnson planned on meeting the Nationals at the airport before traveling to Anaheim with them, so maybe he caught the final few innings on a television screen at O’Hare. If he did, he saw Espinosa, one of the young Nationals players who made the job had so desirable for him, flash his immense talent.

The seventh inning began, like most others for the Nationals, with two quick outs. Michael Morse drew a walk, bringing Espinosa to the plate. Espinosa blasted the first pitch foul, a few feet from a home run. Two pitches later, Humber hung a slider, and Espinosa destroyed it. The ball landed over the visitor’s bullpen in right field. Espinosa’s 14th home run gave him the National League lead among second basemen and gave the Nats a 2-1 edge.

“I didn’t know I’d get another chance to hit one out,” Espinosa said. “But I knew he’s going to come at me. He just made one mistake.”

Tyler Clippard dodged a bullet to escape the seventh, watching as Paul Konerko hammered what appeared to be a two-run homer toward left field, only for the wind to knock it down, settling in Hairston’s glove on the warning track. Sean Burnett pitched a 1-2-3 eighth, Drew Storen recorded his 19th save in the ninth.

“An awesome guy, a great baseball guy,” Storen said. “We’re going to miss him. I’m just glad I could seal that one for him. Mac’s one of my favorite people I’ve ever met in this game. It really means a lot to have him be part of my career.”

He went 2-1 as the fourth manager in Nationals history, a brief, bizarre stint Rizzo and players admired him for serving. “This is a guy that stepped in as a huge team player and stepped in to manage the club in trying times,” Rizzo said.

“It’s been a tough couple days, but he’s handled everything as professionally as he possibly could,” Burnett said. “Kind of sad not to see him be around any more. It’s unfortunate that one man’s decision kind of affects other people’s lives.”

In mid-May, during a series on the road against the Marlins, McLaren could sense the strain of a tenuous contract situation wearing on Riggleman, the building frustration and tension.

Riggleman looked like a man “out on an island by himself,” McLaren said. McLaren, then the bench coach, had decided to play his loyalty with Riggleman.

“Jim, I’m all in with you,” McLaren told him then. “If you leave, I’m going to leave.”

On Thursday, when Riggleman resigned, Rizzo met with each coach individually in a conference room. He asked McLaren, who was blindsided by Riggleman’s resignation and, his words, “a bundle of emotions,” if he would manage the team on a short-term basis. He told him he would, but then he would resign.

“I’m a very emotional man,” McLaren said. “I kind of wear everything on my sleeve. But I think everybody’s good now. It’s been fun. The Nationals have treated me very well, and it’s time to move on.”

Over the course of several conversations, Rizzo convinced McLaren to stay with the organization and take a scouting job. Before the game, McLaren met with players in small groups, thanking them and telling them himself he would leave.

Several times over the past three days, tears have welled in the corners of McLaren’s eyes as he addressed reporters. He admitted he still feels the strain from being fired in Seattle, where he was the manager for the first half of 2008.

Following the game, McLaren flew not with the team to Anaheim, but home to Washington. His position as a front-office scouting assistant will take him away from the dugout, where he spent the majority of the past three decades. Sunday, he’ll always have.

“If I never manage again, I won,” McLaren said. “So I’ve got that.”