OAKLAND -- Daniel Mengden delivered his second consecutive strong performance Thursday in a 5-1 loss to the Rangers -- an outing A's manager Bob Melvin said was "wasted."
The A's No. 13 prospect allowed two runs (one earned) over 6 1/3 innings while striking out a career-high seven in his second Major League start. He retired 15 straight until the seventh inning, in which both runs scored, including a leadoff homer by Ian Desmond.
It was the lone blemish in an otherwise encouraging performance.
"Mengden was terrific," Melvin said. "Typically when you put together two outings like that, you're 2-0, maybe a no-decision in a game like this where it's a well-pitched game. It's unfortunate you pitch that well and we waste two pitching performances like he's given us."
Mengden is now 0-2 with a 2.25 ERA, following up his debut vs. Cincinnati on Saturday, when he gave up two runs and struck out five in 5 2/3 innings.

"It's always great having a pitchers' duel," Mengden said. "[Colby Lewis] pitched a good game. I'm just trying to get my feet wet and get more comfortable."
Mengden matched Lewis, who took a perfect game into the eighth and a no-hitter into the ninth, for the first six innings, throwing six scoreless frames. Melvin showed trust in the rookie in the seventh, leaving him in to face lefty Mitch Moreland despite putting runners on first and second after the Rangers struck for two runs.
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But Moreland singled, and Mengden was pulled in favor of Ryan Dull, who promptly struck out Elvis Andrus and Bobby Wilson to strand the bases loaded. Melvin said he would've left Mengden in to face Andrus if the righty had retired Moreland.
"I thought he earned it," Melvin said.

Mengden kept the Rangers off balance, primarily utilizing a low-90s fastball and his curve, striking out five straight over the fifth and sixth innings. 
"It's impressive," catcher Stephen Vogt said. "He's a confident kid with really good stuff. That's a good mix. He knows how to pitch, he knows where to put the ball. Obviously he's made minimal mistakes. Two mistakes in two starts is pretty good."
Mengden had a slim margin of error to work with Thursday, but he said he feels more comfortable and trusted all four of his pitches.
"Obviously it's frustrating," Vogt said. "It's never fun when you have your starter go that deep and give you a chance to win [and we lose the game], let alone getting no-hit into the ninth."