TUCSON - The move may simply have been made to keep the Rockies from getting a good look at Randy Johnson. Or it could be something more.

Manager Bob Melvin said the Big Unit will pitch in a minor league game on Wednesday instead of the big league game against Colorado.

The move is significant because it would allow the Diamondbacks to backdate Johnson’s move to the 15-day disabled list, the full nine days allowed into spring training, keeping him out of only six days of regular-season action.

If Johnson pitched against the Rockies, he wouldn’t have been eligible to come off the disabled list until April 11. Melvin said he would know more after seeing how Johnson responds to his longest outing to date on Wednesday.

“It’ll be a little clearer picture about how our rotation is going to set up going into the season after his game,” Melvin said.

At this point, Johnson’s earliest return would be April 6, the final game of a three-game series at Colorado.

A LITTLE BETTER

Micah Owings’ overall numbers were better, but he’s still battling command issues as spring training winds down. He walked four batters — all in the first three innings — in his 5 1/3 innings of work on Monday against San Francisco.

Despite the walks Owings allowed just one run through the first five innings before giving up back-to-back home runs to Fred Lewis and Bengie Molina in the sixth.

Owings has consistently fallen behind in the count against hitters and his Cactus League ERA is 9.77.

“I’m not concerned,” Owings said. “I don’t think anybody should be concerned. The minute you start getting concerned then you start pressing.”

STILL DECIDING

The first three starters of the year have been determined — Brandon Webb on opening day, followed by Dan Haren and Doug Davis — but an off-day between the first two games of the season would allow Melvin to skip the fifth starter spot if he so chooses.

At this point he would like to throw a fifth pitcher — presumably Edgar Gonzalez — to give his pitchers an extra day off and keep them fresh.

“We rely on our starters quite a bit for innings, so if we can give them a blow” we’ll do so, Melvin said.

FIRST TASTE

Left-hander Doug Slaten (knee) pitched in his first game of the spring, allowing no runs and one hit in one inning. The very first batter attempted a bunt, which Slaten fielded and threw to Conor Jackson at first base for the out.

“He really wanted to test me because he bunted it right back at me,” Slaten said. “He didn’t think I could do it.”

SHORT HOPS

Miguel Montero took batting practice on Monday, and he could get into a game in the next 4 to 6 days, Melvin said.

Giants manager Bruce Bochy was ejected in the seventh inning for arguing a call at first base.

Dustin Nippert allowed the tying run to reach third base in the ninth inning, but got two strikeouts and a ground out to end the contest.

Pitchers Billy Buckner and Leo Rosales were reassigned to minor league camp before the game.