Since June 24, when Detwiler was reinserted into Washington's starting rotation, the 26-year-old lefty has been solid. He has a 2.55 ERA in seven starts during that span, and Washington is 5-2 in those games.
Detwiler is coming off arguably his best start of the season, throwing seven scoreless innings against the Phillies on Thursday. He gave up just three hits and walked two while striking out three. He will look to keep his recent string of success going Tuesday against the Astros at Minute Maid Park.
"It's just falling into a routine, and that's when I get comfortable, when I can fall into my routine," Detwiler said. "I know I'm going to be here starting now, so it makes it a little easier."
The Astros will try to counter Detwiler with righty Jordan Lyles, who hasn't made things easy on himself of late. His ERA has gone up in each of his last four starts.
Last time out, Lyles went five innings against the Brewers, giving up nine runs -- seven earned -- on nine hits. He gave up six runs in the fifth inning in that game after holding the Brewers to three runs in the first four innings, when the Astros made four errors.
"I was proud of myself for doing that early on, but what sticks out is the big inning," he said after that start.
The big inning has been an issue for Lyles at times this season. His ERA in the fifth inning is 16.34 and in the sixth it's 8.31, while his ERA in the first three innings is 2.60.
Nationals: Izturis joins club on Tuesday
A day after Washington claimed him off waivers, Cesar Izturis will join the Nationals on Tuesday. The team placed a claim on Izturis in order to bolster the club's middle-infield depth with Ian Desmond on the disabled list, Mark DeRosa sidelined with a groin injury and Danny Espinosa banged up following a head-first slide on Sunday.
Izturis hit just .235 in 57 games with Milwaukee this season, but played well during his last 16 games, hitting .294 with four doubles, a triple and a home run. The Nationals placed DeRosa on the 15-day DL and designated left-hander Atahualpa Severino for assignment to make room on the roster for Izturis, who will be playing for his eighth big league club.
"To have him available, it must be our year. Real good defender," manager Davey Johnson said. "It's like having spot starters in the bullpen. I sleep better."
Astros: Lowrie, Castro progressing
While there is still no timetable for Jed Lowrie's return, manager Brad Mills said the shortstop has improved range of motion in his right knee since he began wearing a new brace in the middle of last week.
"We want to get some of that muscle strength back," Mills said.
Catcher Jason Castro, who has been sidelined since July 8 with a right knee injury, is also improving. He caught five innings on Sunday for Double-A Corpus Christi. Castro will catch seven innings in a pair of games for Triple-A Oklahoma City. Provided he doesn't experience any pain in his knee, he will then play nine innings in back-to-back games before the team considers reinstating him from the disabled list.
After Monday's series-opening loss, the Astros became the fourth team in the last 60 years to go 4-31 over a 35-game stretch during a single season, according to Elias.