PHOENIX -- Jordan Lyles didn't act his age on Sunday.
He didn't pitch like it, either. Under different circumstances, a young pitcher like Lyles, who won't be 22 for another three months, would be honing his craft in the Minor Leagues. Instead, he's in the big leagues learning how to pitch on the highest level.
Against the D-backs, Lyles, the youngest starter in the National League, mostly held his own. And if not for one costly inning in the middle of the game, he appeared on his way to his third victory of the season, instead of an 8-2 loss in the series finale at Chase Field.
Sunday's loss was the sixth in a row for the Astros as they finished 1-9 on their 10-game road trip. They return to Houston for seven games against the Reds and Pirates starting Monday, looking to recover from their 19th loss in the last 21 games.
"We are glad we are going home," Astros manager Brad Mills said. "It seems like forever since we have been home. There are some things we can build on as we move forward, but there are some things that we are working on that we want to make sure we get cleared up as well."
It didn't have to be this way for Lyles and the Astros. The scoreboard only told part of the story.
Lyles retired the first three batters he faced, but gave up a solo home run to D-backs' left fielder Jason Kubel to start the second inning, tying the game at 1-1. Justin Maxwell's home run in the top of the second, his ninth of the season, had given the Astros a 1-0 lead.
Lyles then got on a roll. He was in control of his fastball, which sat between 92 and 93 mph, and his secondary pitches were also working.
After giving up the homer to Kubel, the right-hander allowed only two baserunners -- Gerardo Parra, who he eventually picked off, in the third, and Ryan Wheeler in the fifth -- until a disastrous bottom of the sixth inning that changed the game.
The Astros pulled ahead, 2-1, in the top of the sixth on a RBI double by Chris Johnson, but the lead would not last.
Lyles retired Parra to start the bottom half, but Stephen Drew, Aaron Hill and Kubel followed with consecutive singles in a span of seven pitches to load the bases.
The hit barrage was halted temporarily by a visit to the mound by pitching coach Doug Brocail, but resumed on the next pitch, a 92-mph fastball that D-backs catcher Miguel Montero hit hard up the middle.
Astros shortstop Marwin Gonzalez corralled the ball and tossed it to second baseman Jose Altuve, but Altuve couldn't hold on. Two runs scored to push the D-backs ahead, 3-2, and Gonzalez was charged with an error.
"I tried to barehand it," Altuve said. "At that moment I thought I could not get it with my glove. I was just trying to catch it. I tried my best, but I could not make the play. At that moment, I thought that was the only chance I had."
It was the second consecutive game that a costly miscue came back to haunt the Astros. On Saturday, Astros starter Dallas Keuchel made a throwing error after fielding a bunt in a crucial five-run inning for the D-backs that changed the complexion of the game and eventually led to an Astros loss.
"If we could have been able to get an out on that ball up the middle, that really would have helped," Mills said. "On a play like that, if you get them both it's a spectacular play, but if you get one, that's huge."
The next batter after Gonzalez's error, Chris Young, hit a three-run home run on a 3-2 count to extend Arizona's lead to 6-2. Lyle Overbay and Ryan Roberts each followed with singles and Lyles was replaced by Wesley Wright with two outs to face Parra.
"One of the reasons I really left [Lyles] out there after the home run was to see if he could get it back right then," Mills said. "I know it was out of the door, then but we are trying to get him to a point to where he will be able to regroup."
The D-backs kept on scoring, as Parra hit a two-run single to cap off the seven-run inning and give the D-backs an 8-2 lead.
"I don't know what it was," Lyles said. "A couple of hits back-to-back and that pitch I made to Montero I wanted a ground ball and got it. He just hit it up the middle too hard. Up until the sixth inning, [catcher Carlos Corporan] and I were doing a good job, but the wheels fell off in the sixth."