ARLINGTON, Texas -- It was 89 degrees at Rangers Ballpark in Arlington at 2:08 Sunday afternoon when Yu Darvish threw his first pitch.
The temperature had nothing to do with his second consecutive subpar performance. His struggles, like always, centered around his fastball command -- and, perhaps, a stiff back, a cold or a virus.
This much is certain: When Yu commands his fastball, he's virtually untouchable; when he doesn't, he's pedestrian.
It's that simple.
For now, any chatter about the weather is irrelevant. Now, the stiff back, cold or virus that caused the Rangers to yank him after five innings is something we should monitor.
Frankly, all I want to know is how long it's going to take Yu to fix whatever prevents him from consistently replicating his delivery, so he can consistently throw strikes.
Yu is too good to last just five innings, especially when the offense gives him a seven-run lead after two innings.
But that's what happened.
Yu allowed seven hits and three runs. He walked three and struck out three in the Rangers' 12-6 win over Toronto.
He did not have a 1-2-3 inning, which is not nearly good enough for a dude with his stuff.
"You know he came up with a stiff back, and it could've been some of the reason he was erratic," Rangers manager Ron Washington said. "I didn't find out about it until after the fifth inning was over and he was in the dugout.
"If he didn't have the stiff back, he would've went out for the sixth. At some point I felt he was going to have a quick inning. We weren't taking a chance once he said his back was stiff, so we took him out."
Considering their $112 million investment in the 25-year-old pitcher, the Rangers take no chances with Yu's health.
"I don't want to label it a sore back like I did something to do it," Yu said through his interpreter. "It's not like I'm dealing with an injury. I feel very comfortable saying I should be able to treat this, nurse it and be strong for my next start."
If David Murphy had not made a sensational over-the-shoulder catch against the left-field wall in the second inning, and Michael Young, playing second base, hadn't snagged a wicked one-hop grounder in the fifth inning to start a double play, Yu's final pitching line would've been a lot worse.
Yu's competitive nature kept him in the game for five innings. Toronto began the game 0-for-8 with runners in scoring position. One of Yu's best traits is that he rarely gives in mentally with runners in scoring position.
He tends to make his best pitches when he needs them most. Opposing hitters are batting just .185 (12-for-65) against him with runners in scoring position.
Of course, he wouldn't have to focus so much on batters with runners in scoring position if he consistently threw his fastball for strikes.
He threw first-pitch strikes to only 10 of the 22 batters he faced. Although he had only four three-ball counts, he consistently pitched behind in the count.
And that's why he had thrown 93 pitches -- 54 strikes -- after only five innings.
Some of Yu's trouble throwing strikes stems from his delivery. The rest of it is mental as he continues to adjust to baseball in America.
In Japan, the hitters chased pitches out of the strike zone more than they do in the big leagues. Here, the hitters are more selective, waiting for a particular pitch in a particular zone they can drive.
In Japan, Yu often used his off-speed pitches to set up his fastball. In the big leagues, pitchers use their fastball to set up the off-speed stuff.
Bottom line: He must throw more strikes because his stuff is so good, most hitters can't touch it anyway.
There's no good reason for a pitcher with Yu's talent to have 32 walks in 56 innings. In his last start against Seattle, he walked four batters, lasted just four innings and threw 96 pitches.
He's walked at least three batters in seven of 10 starts. Opposing batters are hitting just .234.
"I know he's better than that, just one of them starts today," catcher Mike Napoli said of Yu's performance. "We got a lot of runs on the offensive side, so it gave him a chance to just battle through it and really try to find it.
"Starters have those days when they really can't find it and you've got to battle. We got him through five innings and we got to our bullpen."
Fine, but we already expect more. At least Napoli didn't mention the heat -- or Yu's back.