Giants manager Bob Melvin insists Willy Adames’ clutch hitting “is going to come.”

It repeatedly did not come in Monday’s 3-1, series-opening loss at Detroit, and Adames’ offensive woes are blindingly reflective of the Giants’ anemic output over the past nine games.

The Giants (31-23) managed just five hits, and none went for extra bases against the American League-leading Tigers (35-20).

Adames went 0 for 4 for a second straight afternoon, and that is not what the Giants banked on when signing him to a seven-year, $182 million deal.

“Obviously, he hasn’t gotten off to the start that he wants to,” Melvin told reporters of Adames after Monday’s game. “You tend to try to do a little too much sometimes when you get in big RBI situations.

“He’s kind of known for that. He hit a ton of three-run homers last year, so it’s going to come. Maybe (he’s) just trying to do too much and swinging a little early in those situations.”

Adames may have hit a career-high 32 home runs (13 of the three-run variety) with the Milwaukee Brewers last season, but his Giants’ initiation has struggled in multiple offensive aspects. His batting average dropped to .205 on Monday, and he is 2 for 32 in the past nine games, none of which the Giants produced more than four runs.

Adames halted the Giants’ most promising rallies in this opener at Detroit, and he came up with a chance to hit three-run homers in both the first and sixth innings. Instead, his at-bat ended each rally. He has five home runs this season, none in the past 10 games.

The biggest rally-killer came in the sixth, when Adames grounded up the middle into a double play, right after three consecutive singles off Tigers relievers by Matt Chapman, Jung Hoo Lee, and Wilmer Flores (which was his team-high 44th RBI).

Adames struck out looking (on an 86-mph slider) to end the Giants’ first-inning threat, stranding Chapman (walk) and Lee (single) at second and third. After a Flores single provided hope for a ninth-inning comeback, an Adames grounder forced out Flores at second, followed by a LaMonte Wade Jr. strikeout and Tyler Fitzgerald’s game-ending lineout to right.

“Every opportunity we had today, we either hit into a double play or didn’t get it done,” Melvin said. “We keep putting a lot of pressure on the key at-bats, and we’re not coming through with them. They obviously did today with the (Riley) Greene at-bat and that was the difference in the game.”

Shortly after the Tigers chased Giants starter Hayden Birdsong, Greene delivered a two-run single to right off reliever Erik Miller to give Detroit a 3-0 lead. Adames, to his credit, turned a double play to end the inning, which started with Birdsong striking out Javier Báez, who then promptly got ejected for arguing the call with umpire Phil Cuzzi.

Tigers starter Keider Montero retired 13 batters in a row after Lee’s flare to left in the first inning. Montero (2-1) entered with a 5.28 ERA.

Birdsong (1-1) impressed but got admittedly tired after throwing 88 pitches in his second start, having excelled in the bullpen to begin his second big-league season. He was pitching a scoreless gem until Dillon Dingler’s two-out single scored Colt Keith, who beat left fielder Luis Matos’ dribbling throw home to Patrick Bailey.

Birdsong got chased one out into the fifth inning, leaving Kerry Carpenter (single) and Gleyber Torres (walk) for reliever Miller, who promptly loaded the bases with a five-pitch walk before yielding Greene’s two-run hit.

Down 3-0 to open the sixth, Chapman and Lee delivered one-out singles off reliever Tyler Holton, followed by Flores’ two-strike, RBI single off the Tigers’ next reliever, Brenan Hanifee. Then came Adames’ double-play groundout.

The Tigers threatened to score first in the opening inning.

Matos got twisted in retreat of Keith’s two-out flyball before it one-hopped off Matos’ mitt and over the wall for a double, on what initially was deemed an error. Matos, making only his fourth start of the season in left field, promptly made amends by snagging Riley Greene’s 357-foot flyout at the wall.

The Giants will send Logan Webb (5-4, 2.67 ERA) up against Jack Flaherty (2-6, 4.39) in today’s 3:40 p.m. PT game, with Wednesday’s 10:10 a.m. PT series finale pitting Landon Roupp (3-3, 3.63) vs. Jackson Jobe (4-1, 4.06).