SEATTLE — Rockies fireballer Jon Gray and his healing foot traveled with the team to San Diego on Thursday night. He will fly with the team to Denver on Sunday night. He will pitch again for the Rockies soon. But he will not, most likely, add to the rotation.

Colorado manager Bud Black said Thursday that a six-man rotation is unlikely.

“No. Right now? No,” Black said. “What you would need is six guys who are good. You can’t have a weak link. They all have to be performing. And if you have a guy who’s pitching really well, then he’s pitching one day later. You want your good guys out there more often.”

Colorado’s 4.30 ERA and .254 batting average against five starting pitchers are at the median of the major leagues, ranking 15th. The Rockies’ ballpark-adjusted numbers, sanding off the hitter-friendly advantage of Coors Field, are even better. It’s a vast improvement over recent seasons, after finishing 26th last year and dead last in 2015.

When Gray suffered a broken left foot in mid-April while fielding a groundball on the mound in San Francisco, he became the second pitcher lost from Colorado’s rotation. Chad Bettis left spring training to confront testicular cancer. The Rockies filled in those positions and an open fifth slot with three rookies: Antonio Senzatela, 22; Kyle Freeland, 23; and German Marquez, 22.

The rookies have excelled, with a collective 3.57 ERA over 29 games. Tyler Chatwood and Tyler Anderson, though, have struggled, with a combined 5.43 ERA.

Gray ran on the field in Seattle on Wednesday for the first time since his injury. He has been running on a treadmill, trying to get his legs in shape. And he will face hitters in a simulated game when he returns to Coors Field next week.

“We’ll ramp up his intensity,” Black said.

But Gray’s eventual spot in the rotation will remain up for debate.

Murphy update. Tom Murphy, out since spring training because of a fractured right forearm, caught an extended spring game for the first time Wednesday, then another Thursday. He will fly from Arizona to Albuquerque on Friday to join the Triple-A Isotopes and begin a rehab assignment Saturday in the starting lineup.

Murphy, who has more potential for home run power than other catchers in the Colorado system, seemed headed for the opening-day roster before he suffered a broken arm on a bat while throwing to second base in a Cactus League game. The Rockies have used two backup catchers behind Tony Wolters in Murphy’s absence, Dustin Garneau and Ryan Hanigan.

Prospect promotion. Infielder Ryan McMahon, who’s among the Rockies’ top minor-league prospects, was promoted from Double-A Hartford to Albuquerque. The natural third baseman added first base to his resume last year, and the Rockies tasked him with learning second base this year.

“When I saw him practice in spring, you could see the baseball player skill set,” Black said. “Good athletic movements, good hands, strong arm, classic swing. He looks the part.”

Nolan corrected. Major League Baseball’s official scorer reviewed video of an error charged to third baseman Nolan Arenado during a May 21 game at Cincinnati and the error was overturned. The score was changed to give the Reds’ Billy Hamilton an infield single. Arenado now has a perfect fielding percentage in 149 chances this season. The hit, though, charged Freeland, the pitcher that day, with an earned run from that inning.

Looking ahead

Rockies RHP German Marquez (4-2, 3.76 ERA) at Padres LHP Clayton Richard (3-6, 4.33), 8:10 p.m. Friday, ROOT; 850 AM

Even with the benefit of pitcher-friendly Petco Park, the Padres’ 4.60 team ERA ranks only 24th in baseball. But Richard is on a mini-roll, posting a 2.40 ERA (four runs allowed in 15 innings) over his past two starts, including a complete game five-hitter against the Diamondbacks on May 21. Marquez has been better, with a 1.46 ERA and a perfect record over his past four starts. After his call-up in late April, Marquez is proving every bit the equal of his streaking rookie counterparts in the Rockies’ rotation.

Saturday: Rockies RHP Tyler Chatwood (4-7, 5.04 ERA) at Padres RHP Jhoulys Chacin (4-4, 5.77), 2:10 p.m., ROOT

Sunday: Rockies LHP Tyler Anderson (3-5, 5.85) at Padres RHP Jared Cosart (0-1, 4.50), 2:40 p.m., ROOT

Monday: Off