ARLINGTON -- Shintaro Fujinami didn’t have to say much when summing up his start on Saturday.

“It was a bad day for me,” Fujinami said.

It was a succinct summation of a night that saw not much go right for Fujinami -- or the A’s -- in an 18-3 loss to the Rangers.

Fujinami lasted just 2 1/3 innings, allowed eight runs on seven hits, striking out two, walking three and uncorking two wild pitches.

“I couldn’t throw strikes with the fastball tonight,” said Fujinami, who threw 72 pitches, 42 for strikes. “I’ll make adjustments with my mechanics and try to do better next time.”

Fujinami struggled out of the gate. The A’s took a 2-0 lead in the top of the first inning highlighted by rookie Jordan Diaz's RBI single, but the Rangers quickly evened it at 2-2 in the bottom half when Adolis García unloaded on a first-pitch slider for a two-run shot off Fujinami.

Texas then broke it open with five more runs in the second. Fujinami recorded one out in the third inning, but that came after he issued a leadoff walk that led to another Rangers run.

“For Fuji, it’s a continual battle with fastball command, having confidence in the fastball and being able to throw it for strikes,” manager Mark Kotsay said. “It was quickly evident that he didn’t have any confidence in his fastball tonight and where he could throw it. He went to the split, and instead of the split being an out pitch, it became his strike pitch, which ... these hitters are really good hitters.

“They can handle a split that’s in the zone at 91 (mph), so it became where he had to throw it down the middle for a strike. Unfortunately, at this level against good hitters, you can’t get away with that.”

Kotsay called it a "step backward" for Fujinami, who had shown some progress in his previous starts. He had a rough A's debut on April 1, lasting just 2 1/3 innings and allowing eight runs, allowed five runs in 4 1/3 innings in Tampa Bay on April 8, before putting together a quality start (six innings, three runs) against the Mets on April 15.

Unfortunately for Fujinami and the A's, that trend didn't continue on Saturday, and by the end of the night Fujinami fell to 0-4 with a 14.40 ERA. He’s issued 12 walks over 15 innings in his four starts.

Kotsay said the organization will evaluate Fujinami’s role going forward.

Asked if Fujinami will start again, Kotsay said: “You’ve got to give me a minute on that. The plan right now is to evaluate -- everything is on the table. We’ll assess it and make a decision, but obviously not tonight.”

Despite his rough start in the big leagues, Fujinami remains one of the more intriguing players on the A’s roster. He can light up the radar gun with his fastball in the triple digits at times, but command remains an issue.

“We’ll dive into it trying to build confidence in his fastball and his ability to throw it for strikes,” Kotsay said. “We’ll continue to grind on our end and coach and hopefully turn this thing around for him.”

After Saturday, Fujinami joined Mike Morgan (1978-79) and Roger Wolff (1941-42) as the only pitchers in A’s franchise history to take a loss in each of his first four career outings.

Fujinami wasn’t alone in his struggles on the mound, though. Adrián Martínez gave up five runs over 3 2/3 innings, and James Kaprielian was tagged for three of his own in one inning. A’s infielder Jace Peterson pitched the eighth and allowed two runs.

Late in the game, all eyes were on García, who was having a career game for the Rangers. He followed his homer against Fujinami with two more against Martínez and had two chances late for a coveted four-homer night. However, García settled for doubles off Kaprielian in the seventh and Peterson in the eighth.

“He got good pitches to hit, and he did what he could do,” Kotsay said of the Rangers' slugger. “I think he has seven home runs on the year now. He hits in the middle of this lineup, I’ve seen him for the last two seasons continue to grow as a hitter, continue to get better and better. He’s a real threat in the middle of the lineup now.”