Blake Treinen allowed three runs in the eighth inning, continuing a slump that has lasted over two weeks, turning a Dodgers lead into a 3-1 loss to the Giants on Sunday at Dodger Stadium.

Up 1-0 to open the eighth, Treinen allowed two singles and a ground-rule double to tie the game before recording an out. Dave Roberts opted to intentionally walk Rafael Devers to load the bases, trying to set up a double play, but still an iffy proposition with Treinen having control problems of late, including two walks in Thursday night’s series opener.

Much like on Thursday, Treinen walked in a run, then a groundout scored another. Three runs were enough to hang the loss on Treinen, his fifth loss in his last seven appearances. During that time he’s allowed 11 runs, nine earned, in only 5 1/3 innings, with more unintentional walks (five) than strikeouts (three).

Treinen has been one of the Dodgers’ best relievers when healthy, and was a big part of last year’s postseason run. He is by no means alone in a very shaky bullpen at the moment, but he hasn’t pitched well enough to continue to pitch in the highest-leverage spots, as he has done on average so far this season.

Emmet Sheehan has compiled as good a résumé as any Dodgers starting pitcher this season, especially of late, all but assuring he will pitch meaningful innings in October even if he doesn’t start.

The right-hander matched career highs with 10 strikeouts and seven scoreless innings, with Sunday having a lot in common with that same combination on August 25 against the Reds which was one of the best Dodgers starts of the season. That night, Sheehan allowed two singles and a walk, and on Sunday against the Giants Sheehan allowed one single and hit two batters. He retired his final 15 batters.

Sheehan has allowed only four total runs in his last five starts, with 42 strikeouts against only seven walks in 32 1/3 innings. He has a 2.86 ERA and 30.1-percent strikeout rate in 72 1/3 innings on the season.

He now has two double-digit-strikeout games this season to go with his three seven-inning games. Sheehan just happens to be lower on the depth chart in a rotation with Yoshinobu Yamamoto, Tyler Glasnow, and Blake Snell, all of whom have multiple of each this season, plus Shohei Ohtani.

Sheehan only needed 84 pitches to get through his seven innings, and received a Yamamotoan level of run support. Trevor McDonald was pitching in his second major league game for the Giants and his first major league start, and held the Dodgers scoreless through six innings.

A walk by Max Muncy started the seventh inning, followed by singles from Andy Pages and Michael Conforto for the game’s first run. Conforto, who played with the Giants the last two seasons, hit .378/.415/.649 with three home runs and 10 RBI against them this year.

But that one single run did not hold up for the Dodgers on Sunday.

With an announced attendance of 46,601 on Sunday, the Dodgers concluded their home schedule with 4,012,470 total attendance, an average of 49,537 per game, leading the league in attendance for the 12th season in a row. They reached four million fans for the first time in franchise history, and the first MLB team to hit that mark since 2008. Bill Shaikin had a nice breakdown of the Dodgers’ attendance and resulting ticket revenue earlier this week in the Los Angeles Times.

Home runs: none

WP — Spencer Bivens (3-4): 3 up, 3 down

LP — Blake Treinen (1-7): 2/3 IP, 3 hits, 3 runs, 2 walks

Sv — Ryan Walker (16): 2/3 IP, 1 strikeout

The Dodgers are off on Monday but start a season-concluding road trip against the Diamondbacks in Arizona on Tuesday night (6:40 p.m. PT, SportsNet LA). Shohei Ohtani will be on the mound for the Dodgers, with Brandon Pfaadt starting for the home team.