SEATTLE -- Their best player’s struggles became pronounced enough that Mariners manager Scott Servais on Sunday tried to give Julio Rodríguez the day off to “unplug.” Their ace looked better in the series finale against the Cubs, but Luis Castillo has now lost six straight starts dating back to the final week of last season. And their most productive hitter of late is headed to the injured list, after Dominic Canzone sprained his left AC joint when crashing into the wall.

Making matters sting even more in the Mariners’ 3-2 loss to Chicago was that Rodríguez was picked off first base to end the game. He entered as a pinch-runner and was initially ruled safe, but a Cubs challenge overturned the play, leaving Rodríguez -- who preferred not to speak postgame -- quite literally up in arms.

“Everybody is going to get fired up, but that's not the play that cost us the game,” Mariners manager Scott Servais said.

It was merely the final blow.

The Mariners had rallies brewing in the seventh and eighth, with two on and no outs in each, but both ended with double plays, via Luke Raley and Ty France, respectively. The eighth was particularly brutal, given that Cubs reliever Héctor Neris -- on the mound here for the first time since a benches-clearing incident with the Astros last September -- walked the bases loaded.

Seattle’s only run production came via Jorge Polanco’s 399-foot, two-run homer in the sixth, the club’s first in its past five home games, which made it a one-run game. It was also the Mariners’ only extra-base hit, and it was part of an 0-for-6 day with runners in scoring position.

“They gave us an opportunity to take the game and the series -- and we just didn't go grab it,” Servais said.

The lack of volume to Seattle’s 6-10 record shows that the “it’s early” adage rings true. But after missing the postseason by one game, the urgency for a fast start that they spoke of in Spring Training hasn’t correlated to the regular season for the Mariners, who are still seeking their first series win.

Castillo cleared his first quality start of 2024 and flashed some of his best stuff when K’ing the side in the third. But he also succumbed to critical hits with two strikes, including an 0-2 double to Dansby Swanson that was followed by a 2-2 homer to Michael Busch. And that didn’t include the error that “La Piedra” was charged in the first, when sailing an awkward throw past France on a swinging bunt from Cody Bellinger that led to an unearned run.

“I think what I can take out of this is that I’m getting better,” Castillo said through interpreter Freddy Llanos.

Quality starts had been the Mariners’ barometer for success, given that they were 5-0 in such games after Friday and had ranked third MLB with 74 quality starts last season, going 55-19 in those games.

But they then lost each of the next two, beginning with Emerson Hancock on Saturday and continuing with Castillo on Sunday, because while their blueprint is rooted in pitching, it also hinges on the offense carrying its weight.

The Mariners are averaging 3.1 runs per game (tied for third-fewest in MLB) and have scored at least four runs -- the threshold needed for victory on Sunday -- only six times. Moreover, they fell to 0-10 when trailing after the sixth inning, and their only comeback win was Rodríguez’s 10th-inning walk-off in the season’s third game. They’re also 0-9 when their opponent scores first.

Canzone’s status -- which will necessitate an IL stint -- could be concerning. He has a team-leading three homers and an .817 OPS, and he suffered the injury when making a remarkable catch, but one in which he didn’t turn to see the wall and slammed into the barrier.

Rodríguez, meanwhile, was sidelined while healthy, but his bright spots in 2024 have been few and far between. He’s hitting .186 with a .441 OPS, and his chase rate, whiff rate, K rate and walk rate all rank in the 21st percentile or lower, per Statcast, tying back to the issues he had during lulls in ‘23.

It’s why Servais preferred not to use him at all on Sunday -- but the stakes proved vital to do so.

“We had opportunities certainly there in the seventh and the eighth,” Servais said. “Julio is our fastest runner. We're certainly going to put him in the game. ... But for me, that's not the play that cost us the game."