SEATTLE -- Given how it started, it’s wildly ironic how it ended.

Luis Castillo set a Mariners record by striking out each of his first seven batters to begin Wednesday's matinee at T-Mobile Park, just two hours after manager Scott Servais fielded questions over how buttoned-up Seattle’s defense has been all season.

• Box score

Yet after the dust settled on a disappointing 9-6 loss to the White Sox, the Mariners were left with arguably their most uncharacteristic showing of the season, a defeat manifested with costly defensive miscues and an earlier-than-anticipated exit by their ace after such an epic beginning. Seattle committed three errors, each of which led to runs, spoiling an otherwise strong start by Castillo and a big day for Eugenio Suárez, who crushed his 1,000th career hit as part of a two-homer day.

“It’s very uncharacteristic of what we normally do,” Servais said. “I do not want to harp on it. The sky is not falling. We had a bad day. We'll come back and play good defense.”

The Mariners had only twice before committed three errors in a game, and on Wednesday, they led to a season-high six unearned runs. If their showing seemed like an outlier, it probably was.

“Very much so,” Servais said.

Mariners’ defensive ranks entering Wednesday (MLB rank)
Errors: 40 (1st)
Outs above average: 9 (9th)
Defensive runs saved: 40 (7th)
Defensive WAR: 0.7 (12th)

Here’s a recap of the three errors that led to runs:

• Suárez, who might be a sneaky Gold Glove Award candidate at third base, watched a ground ball from Seby Zavala scoot through his legs to lead off the sixth inning. Zavala reached, then scored as the inning spiraled away from Castillo. Suárez later missed a tough chopper by Eloy Jiménez that led to a down-the-line double on a ball that initially looked like it was heading foul. And all of a sudden, Seattle’s 4-0 lead -- built in large part by Suárez’s towering two-run homer in the fourth -- was quashed.

• With the score tied in the eighth inning, catcher Curt Casali sailed a throw into the outfield on a stolen base by Leury Garcia, who easily reached third on the mishap. Garcia was already well on his way when Casali fired, in part due to the lengthier delivery by Mariners reliever Diego Castillo. Garcia scored on Gavin Sheets’ Baltimore chop to short.

• With Seattle trailing by one in the ninth, Chris Flexen overthrew first base on a sacrifice bunt by Zavala with no outs and two on, which allowed a run to score from second. Flexen later surrendered a sacrifice fly to José Abreu that would have been the third out instead of the second had it not been for the mishap.

It was an all-around off afternoon, and one that the Mariners would like to quickly flush.

“That’s just kind of part of baseball,” Castillo said through team interpreter Freddy Llanos. “Sometimes, there are bad moments. Sometimes, there are good moments. A lot of times, there are more good moments than anything. We just have to turn the page.”

The day’s bright spot was the righty’s early showing. Castillo’s seven consecutive K’s tied Mark Langston for the franchise record for the most at any point in any game, dating back to June 15, 1984, against the Rangers at the Kingdome.

Seattle’s previous high to start a game was five, done by Michael Pineda on July 9, 2011. Six others had four K’s to begin a game, including Logan Gilbert (twice), Félix Hernández (twice), Langston (twice), Justus Sheffield, Taijuan Walker and Pineda. Castillo was two shy from tying the MLB record for most strikeouts to begin a game, the nine set by Miami’s Pablo López last July 11.

Perhaps just as impressive about Castillo’s effort is that he carved through the White Sox with his entire arsenal. He generated punchouts on his four-seam fastball, slider and changeup over his first seven hitters, with only one of the K’s being backward for a called strike three.

The Mariners acquired Castillo ahead of the Trade Deadline to help fortify a rotation that was already one of the more consistent in the American League. He has a 2.70 ERA in seven starts since the trade, holding hitters to an opposing slash line of .226/.282/.352 (.634 OPS).