SURPRISE, Ariz. -- Bartolo Colon pitched 5 1/3 scoreless innings for the Rangers in Thursday's 5-4 split-squad loss to the Mariners.
That makes him the leading candidate to be the Rangers' Pitcher of the Week, but it may not be enough to win a spot on the pitching staff for Opening Day. That decision is pending as the Rangers discuss the composition of the roster in the waning days of Spring Training.
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"Thank God I felt really good today," Colon said. "I was just throwing strikes. I felt really good with my control. I feel really good about it. I feel like it is one of the best Spring Trainings of my career."
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Colon's outing comes when the Rangers' top four starters -- Cole Hamels, Mike Minor, Matt Moore and Doug Fister -- allowed a combined 23 runs over 15 innings this week. That includes Hamels working in a Minor League game.
Minor, in the other half of the Rangers' split-squad evening, allowed six runs in 5 1/3 innings, though he finished strong by retiring the last 10 batters he faced.
Manager Jeff Banister said he was "happy" and "encouraged," and Minor still appears to be a lock for the rotation.
"His stuff looked good," Banister said. "Fastball … nothing is straight, the breaking ball is swing and miss, and his changeup is getting to be a better pitch."

Colon is not described as electric. He relies on a sinker and his ability to throw strikes. But he is still showing he can be effective.
Colon could also make the rotation if the Rangers decide Martin Perez is not fully recovered from a broken bone in the tip of his right elbow. He is scheduled to pitch on Friday night against the Padres, and that may be the final test for him.
Otherwise, the best chance for Colon would be in the bullpen as a long reliever and spot-starter. The last option would be to go to Triple-A Round Rock and continue to start there. A move to the Minors would likely depend on whether there were opportunities on other big league clubs, because Colon has made it clear he wants to continue to pitch in the Majors.
"It's out of my control," Colon said. "Whatever the team decides, I will see at that point what I decide. I feel good where I am at."

Rangers evaluate Centeno, Tocci
Carlos Tocci was 1-for-3 as the Rangers' center fielder and leadoff hitter against the Mariners. Catcher Juan Centeno was 3-for-4 with a home run in that game. It was a good night for both players to stand out, because the Rangers have decisions pending on both.
Tocci is a Rule 5 pick from the Phillies who has to make the team or be offered back to Philadelphia. The Rangers are trying to find a way to keep Tocci because he is a superior defensive outfielder. He wouldn't displace Delino DeShields in center, but the Rangers are still reluctant to lose such an asset.
Centeno is the leading candidate to be the backup catcher and is out of options. He has to make the team or be exposed to outright waivers. The Rangers are waiting to see what other catchers might be made available as clubs make their final cuts. Cameron Rupp of the Phillies is a name that has been brought up, but Centeno is still the likely guy to be the Rangers' backup catcher.
Rangers beat
• Left-handed pitcher Anthony Gose is scheduled to make his first appearance in a Cactus League game on Friday against the Padres. He was returned to the Rangers by the Astros as a Rule 5 Draft pick on March 9.
• Infielder Eliezer Alvarez, who was claimed off waivers from the Phillies, has been optioned to Double-A Frisco.
• The Rangers honored members of the Class A Advanced Down East Wood Ducks before Thursday's game. The Wood Ducks were co-champions of the Carolina League last year with the finals being canceled by Hurricane Irma.
Up next
Perez will make his second start of the spring when the Rangers face the Padres at 8:40 p.m. CT Friday in Peoria. He allowed one run in five innings in his last start against the Angels. The matchup will be available on MLB Network and MLB.TV.
Cole Hamels is scheduled to pitch on Saturday against the Indians.