BRADENTON, Fla. -- Curious about how important to their dreams the rest of the Pirates consider A.J. Burnett? Your answer was the spontaneous cheering that broke out among them as Burnett walked off McKechnie Field's mound Saturday morning following a 40-pitch simulated game.

That reaction also spoke for Burnett's performance in his first opposition in about a month of live batters, this time on his road back from March 2 surgery on a fractured orbital bone.

"For them to clap when I walked off ... they were happy to see me out there as much as I was happy to be out there," Burnett said. "Them being out there and acting like that makes it fun."

Spring Training
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Calling it a "great day," Burnett threw all his pitches from behind the protective screen during two, 20-pitch innings, displaying enough command for catcher Michael McKenry to afterward call him "game-ready."

"It was a big step. I felt strong, there was good action on everything," said Burnett, whose next tentative step will be a true simulated game on Tuesday against Minor Leaguers in Pirate City.

"Next time will be more important," Burnett said. "It will be more game-like, without a screen, moving around, reacting to ground balls and bunts."

His reaction -- and the reaction of others to him -- raises the question of whether Burnett might blow up the original prognosis that his recovery into game-ready condition would take 8-to-12 weeks.

"I'm definitely closer now than when I got hurt [on Feb. 29]," Burnett said. "They have a schedule to follow the best we can, but it's all in pencil. That's a good thing. Maybe I've opened some eyes and am more ready [now] than they thought I'd be."

McDonald inspired by Hurdle's team message

BRADENTON, Fla. -- Pirates manager Clint Hurdle dropped the flag on the run-up to the season in his daily pregame clubhouse meeting, telling players it was time to "compete."

Hurdle took the message lightly. "I wouldn't make too much of that. We're always out there to compete," he said.

But James McDonald took it to heart. The right-hander, who previously had the most shaky spring of any starter, on Saturday had the most masterful performance, holding the Astros hitless for 5 1/3 innings and winding up with a two-hitter through seven of the Bucs' 5-4 loss in 10 innings.

And zero walks. Only once in 47 regular season starts has McDonald gone seven innings without issuing a walk.

"We had that meeting this morning," McDonald said, "and Clint said it was time to start putting it together, to go out there and compete, it's no longer time to just work on things. So I went out there like it was a regular game.

"I saw what can happen when you execute pitches. I was throwing at guys, saying, 'If you hit it, you hit it. But if you don't, it's strike one.'"

McDonald was slated to work six innings, but was so short of his 90-pitch target that he kept the ball for the seventh. He wound up with precisely 90 pitches.

Mercer among Bucs' latest roster moves

BRADENTON, Fla. -- Infielder Jordy Mercer was optioned to Triple-A Indianapolis on Saturday morning by the Pirates, who also cut three big league veteran pitchers who had non-roster invitations to Spring Training.

Right-hander Shairon Martis and left-handers Jo-Jo Reyes and Doug Slaten, along with catcher Jose Morales, were reassigned to the club's Minor League camp.

The moves left 34 active players -- including four remaining non-roster candidates -- in the Bucs' big league camp eight days before the club packs up and heads north.

Mercer is in line to play second base at Indianapolis, according to Pirates general manager Neal Huntington, to allow more development time at short for Chase d'Arnaud, an early cut.

"Jordy is more accomplished at short," said Huntington, who could envision Mercer joining the Pirates later this season if he hones his versatility. "He could be one of those guys who breaks into the club bouncing around as a role player. His comfort level at second and third will be important to him. He's a candidate to come up at some point this year."

The reassignments of Reyes and Slaten focused the battle for a left-handed relief job between Daniel Moskos and Tony Watson. Manager Clint Hurdle has left open the possibility of carrying two lefties in his bullpen.

Morales could be Burnett's batterymate

BRADENTON, Fla. -- Jose Morales' strained left oblique made him the leading forgotten man of Spring Training. In fact, the catcher with limited big league experience was one of four non-roster players reassigned on Saturday to Minor League camp, without ever having set foot on the field.

But Morales might have an important role ahead of him: He could be A.J. Burnett's first Pittsburgh batterymate when the veteran right-hander's rehab reaches the game stage.

The switch-hitting catcher took his first swings from the left side on Saturday. His first game action will come after the Pirates have already broken camp, in an extended spring training game in Pirate City. The first pitcher he catches, thus, could be Burnett, who despite his encouragingly speedy recovery from eye surgery still is expected to be left behind for a spell.

"Yeah, that could happen," Morales said. "I'm really looking forward to getting some game at-bats. It's been a strange spring."

Morales was injured during the Pirates' mini-camp in January. He turned 29 four weeks ago, and is still looked upon as someone who, once recovered, could help the Pirates both with his versatile bat and his catching.

Worth noting

• Pedro Alvarez tested the discomfort in his left knee by participating in pitchers' fielding practice Saturday morning, and said the knee "felt good."

"I'm just resting it, keeping it iced," Alvarez added.

• The Pirates' blown ninth-inning leads in back-to-back games had something in common: Daniel McCutchen absorbed Detroit's six-run ninth on Friday in his second inning of work, and Ryota Igarashi squandered Saturday's 4-1 lead over Houston while pitching on a second straight day for the first time. "We've got to stretch guys out, get them to the point they can pitch more relief innings," manager Clint Hurdle said.

• Josh Harrison went 2-for-4 on Saturday, which meant both his average (.520) and on-base percentage (.571) took a dive.

• Daniel Moskos finished up Igarashi's tough inning with a pair of strikeouts, extending the left-hander's spring without an earned run allowed to seven outings covering 7 1/3 innings.