The 22-year-old Marlins lefty, who has just 122 days and 74 1/3 big league innings under his belt, took a major stride in regaining command of the strike zone.
In four innings against the Nationals on Friday, the 6-foot-6 former first-round pick gave up one run on four hits, but his key statistic was one walk. It was a far better showing than the five walks and a hit batsman he had in his previous start, a three-inning stint against the Red Sox.
"I felt good out there," said Miller, who threw 52 pitches, 31 for strikes. "The last outing didn't leave a very good taste in my mouth. I think I went back to pitching like I know how to pitch when I'm pitching my best. I felt good. I felt comfortable out there today. That's not necessarily a term I'd use after the last outing I had."
The one walk he issued, to Alex Escobar in the second inning, came with a man on second and one out. Since he was behind in the count, Miller worked carefully to Escobar and ended up getting out of trouble, thanks to right fielder Jeremy Hermida throwing out Nick Johnson at the plate on Wil Nieves' single.
After his previous start, when only 23 of 53 pitches were strikes, Miller said he didn't really do anything new to his mechanics.
"The best way to describe it is I fell back into some bad habits, some old habits, and I am just trying to get back to the direction I wanted to go," Miller said of what went right on Friday in Florida's 3-2 victory.
Injury updates: Scott Olsen is scheduled to throw off flat ground on Saturday or Sunday. The left-hander, who was scratched from his start on Wednesday, is battling shoulder tendinitis.
"We'll see where he's at," manager Fredi Gonzalez said.
Olsen's sore shoulder isn't believed to be serious.
Righty Sergio Mitre threw off flat ground for the second straight day.
Mitre experienced tightness in his right forearm muscle during a Feb. 28 start. He threw for the first time on Thursday, and followed that up with a pain-free session of light throwing on Friday.
Who's on first? On Friday, it was Dallas McPherson.
Experimenting with ways to get him more playing time, McPherson made his first spring start at first.
McPherson is competing for the third-base job with Jose Castillo and Jorge Cantu, but he also has some playing time in the big leagues at first. In all, he played six games there while with the Angels in 2006.
McPherson makes it clear that he isn't taking away first baseman Mike Jacobs' job.
"First base is pretty secure," he said. "There are three of us, and they've got to get us at-bats. Cantu has played first, or Castillo can play second some. Whatever they have to do to get us our at-bats."
McPherson had the biggest at-bat of Friday's game, as he connected on the decisive home run.
McPherson has tremendous power potential, but he's working back into game shape. He missed all of last year as he recovered from back surgery.
"If you can play two, three or four positions, that helps, without a doubt," he said.
Some of the challenges for him at first base are angles off the bat, and where to go on cutoff plays.
"I don't think they were expecting me to be [slick-fielding] Doug Mientkiewicz out there today," McPherson said.
Carroll delivers: Brett Carroll's fortunes with the team pretty much are directly connected to how he hits.
Once his bat is ready to perform regularly at the big league level, he likely will be a Major League outfielder for years to come. Defensively, there is no disputing the 25-year-old's talents. He can play all three positions and his throwing arm is the strongest in the organization.
Competing for a roster spot in camp, Carroll helped himself on Wednesday with a key double in a win over the Orioles. For the spring, he's batting .400 (6-for-15).
"My bat definitely needs the most focus," Carroll said. "My defense, I've been fortunate to be blessed with a strong arm."
A year ago, Carroll split time between Double-A Carolina and Triple-A Albuquerque. He hit .270 in 100 at-bats at Albuquerque, compared to .314 in 318 at-bats at Carolina.
Carroll also got a taste of the big leagues, appearing in 23 games (batting .184) with the Marlins.
Travel squad: With two games set for Saturday, the Marlins will be dispatching players to Port St. Lucie, Fla., to face the Mets, and to Fort Myers, Fla., to take on the Red Sox.
Among those making the trip to Fort Myers will be Hanley Ramirez, Jeremy Hermida, Cameron Maybin, Alfredo Amezaga, Cody Ross, Chris Coghlan, Jose Castillo and McPherson.
In an interesting twist, Ramirez will lead off against Boston's Josh Beckett. The two were traded for each other after the 2005 season.
Dan Uggla, Mike Jacobs, Josh Willingham and Jorge Cantu are scheduled to make the trip to Fort Myers.
Up next: The Marlins have their final split-squad day on Saturday with two away games. Gaby Hernandez starts at Fort Myers against the Red Sox, who are turning to Josh Beckett, at 1:05 p.m. ET. In Port St. Lucie at 1:10 p.m., Chris Volstad will face the Mets, who will send Mike Pelfrey to the hill.
Joe Frisaro is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.