Rockies manager Bud Black’s plan was for the lineup, or at least the top half, to be his simplest duty. But the Rockies are making their second change after a slump and an injury to original leadoff hitter David Dahl.

In 12 games atop the order, right-handed-hitting Garrett Hampson, who supplanted Dahl before Dahl went to the injured list with a lower back strain, put up a solid .275/.351/.431 slash line. But in Thursday’s 10-8 loss to the Astros and again on Friday in the series opener at Dodger Stadium, left-handed-hitting Raimel Tapia batted first.

Tapia, who has hit mostly seventh, had a single and a career-high four walks Thursday. In nine games leading into Friday, Tapia slashed .414/.541/.517. The turnaround occurred after he didn’t start a few games, worked on pitch selection, tweaked his stance to open his lead foot toward first base and returned to a leg hover/kick that he had agreed to abandon in Spring Training.

Was returning Tapia to the top spot, with Hampson not in the lineup for a second straight day, strictly as a split matchup against Dodgers righty Walker Buehler, and will it hold throughout a series in which the Dodgers will not start a lefty? If Tapia stays at the top, does Hampson go lower in the order, or will he be placed higher as part of a greater shuffle? Were there bad signs in Hampson’s last three starts (1-for-12, five strikeouts)?

It bears watching each game, although Black leans toward playing the hotter hand first.

“You can see them both in the lineup, for sure,” Black said. “You saw that recently, just up until yesterday when ‘Tap’ led off. 'Tap’ has had a nice little run here. He’s getting on base at over a .400 clip, hitting over .300 and having great at-bats. It’s practical and makes sense for him to lead off tonight, and we’ll see what we do moving forward.

“Tapia has had experience as a leadoff hitter in the Minor Leagues. He feels comfortable there. I can see this continuing as long as his performance continues to be where it is right now. But that’s fluid.”

Harvey hurt, but hopeful
Righty Joe Harvey left Thursday’s game after one-third of an inning with one hit batter, and Friday was placed on the 10-day IL with a right elbow strain. Black said early reports were that the injury was mild.

“We’re going to continue to assess it, but it doesn’t look as though anything impending or long-term might affect Joe,” Black said. “It tightened up yesterday on him after he got into his inning. It was a gradual tightening over a three- or four-pitch situation and he felt on the safe side to come out of the game. His fastball velocity dropped to 90 mph, and Joe is usually a guy who throws 95.”

Righty Tyler Kinley, who has a 5.00 ERA in 10 games, put forth a good argument for work in close games with his solid 1 2/3 innings against the Astros on Thursday, which included a pickoff of the runner he inherited.

Lefty James Pazos, sent down to the alternate training site with a 17.18 ERA in four games, was recalled to replace Harvey on the roster.

Back on track
The late bullpen has been unsettled because of injuries to Scott Oberg and Wade Davis, but it looks as if the Rockies have dodged a potential problem. Righty Carlos Estévez threw two spotless innings with two strikeouts against the Astros on Thursday -- his first appearance since he was hit on the back of the hand by a line drive on Sunday.

“He threw the ball great yesterday -- came in in the eighth, in a game that was 10-7, and he kept it right there through two innings,” Black said. “He had had three days off from the time he got hit in the back of the hand, so his elbow, his shoulder, his body, were fresh to pitch.”

In 12 2/3 innings this year, Estévez has a 2.84 ERA with 10 strikes vs. three walks.

Getting up to speed
Black sees reason to be careful with top prospect Brendan Rodgers, who went 1-for-2 off the bench Wednesday but 0-for-5 with two strikeouts Thursday in his first start since being recalled from the alternate camp. Rodgers, who didn’t start Friday, looked to be playing catchup to Major League intensity.

“I’ve always maintained there’s a difference between the Minor Leagues and the Major Leagues -- as it relates to Brendan, it’s not an easy question for most guys,” Black said. “But I do think there’s a little bit of a bigger gap this season, because they’re going from intrasquad games to Major League pitching.”