PHOENIX -- Left-hander Wandy Rodriguez has been classified by the Pirates' medical staff as "not likely" to be able to start against the Reds this weekend.
Rodriguez departed with left hamstring tightness in the third inning of his Monday start, and on Tuesday, he underwent an MRI which showed a strain of the hamstring.
The lefty had been tentatively considered to start the Sunday finale against Cincinnati at PNC Park.
Manager Clint Hurdle was not yet prepared to name a replacement starter for Rodriguez -- or to definitely rule him out.
"We're gonna give Wandy another rehab work day," Hurdle said after Wednesday's game. "We'll get him out to the park Friday, and should have a decision sometimes that afternoon or evening."
If he can't go, candidates for that spot start include pitchers on the current staff -- Jeanmar Gomez, Chris Leroux or Justin Wilson -- or someone being recalled from Triple-A Indianapolis.
Marte red hot atop Bucs' batting order
PHOENIX -- If the Pittsburgh offense was a stage play, it would still be in the off-Broadway rehearsal stage. The opening act, however, has already been boffo -- Starling Marte is a best-case scenario unfolding atop the Pirates' lineup.
The dynamic left fielder had his fifth consecutive two-hit game on Wednesday, and drove in his fourth run of the season. It's been Marte -- he improved his batting average to .333 -- and the smidgens -- the rest of the team had a .128 average coming into the game.
While he waits for the rest of the batting order to come to order, manager Clint Hurdle has the luxury of choosing which iconic leadoff batter he wants Marte to emulate.
"One thing we're mindful of -- we want this kid to be aggressive in the strike zone. We're not looking for him to become Maury Wills," Hurdle said. "More of a Rickey Henderson-type leadoff hitter.
"His at-bats have continually cleaned up, throughout Spring Training into the season. He gives us a spark -- an explosive spark -- at the top of the lineup."
With Marte, there is a lot more, obviously. Speed on the bases, defensive range and arm.
"The excitement when he gets on base, we've already seen. It's a good package," Hurdle concluded.
Melancon's bounce-back year off to good start
PHOENIX -- Mark Melancon has been around the Major League block a few times. This, as they say, is not his first rodeo.
However, the 28-year-old righty has never ridden that bucking bronco of big league hitters as smoothly. He has thrown blanks in his first five appearances with the Pirates, allowing only two baserunners in five innings.
And, Melancon says, there is nothing accidental about these first strides on the comeback trail from a 2012 season in which he had a 6.20 ERA out of Boston's bullpen.
"I learned more about my delivery and about pitching in general in a month of Spring Training than I have my whole pro career," said Melancon, whose career began with his 2006 First-Year Player Draft selection by the Yankees.
Melancon has also been through the Houston and Boston organizations without getting the benefit of the type of instruction offered this spring by Pirates pitching coach Ray Searage and Jim Benedict, a special assistant to general manager Neal Huntington, whose specialty is pitchers.
"He brought awareness to some of the things in my delivery which, honestly, I haven't really yet changed," Melancon said of Benedict. "It's a work in progress, and I'm just glad I'm aware of it, so in the long run I can deal with it and be that much better."
It's not a big thing. Just those "little tiny things" that can make a difference, like Melancon's "leg kick and the path it takes."
"People in the big leagues expect you to know everything and just do it," Melancon said. "There's not a whole lot of learning."
The Pirate City School of Pitching appears to be an exception.
• Thursday will be the Bucs' final off-day during the month of April. They are scheduled to play 20 straight games until the next day off, on May 2.
• Brandon Inge (cracked right scapula) went 0-for-4 on Tuesday, and is 2-for-18 six games into his rehab assignment with Triple-A Indianapolis. Wednesday was Inge's first day of eligibility to come off the 15-day disabled list.
• The D-backs weren't sorry to see Garrett Jones missing from the Pirates' lineup on Wednesday, with a left-hander, Wade Miley, on the hill. Jones has a lifetime average of .353 in Chase Field, with three homers and 10 RBIs in 15 games.
• The Pirates' starting lineup on Wednesday -- even with Marte (10-for-32, .313) atop it -- had a collective .167 batting average entering the game.
• A.J. Burnett, scheduled to start Friday night's first meeting with the Reds this season, on the seven Pirates batters hit by Cincinnati pitchers last season: "Obviously something is going on there. That's not our priority. Our priority is to win baseball games. So we'll take care of business when we have to."
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.