WESTFIELD — The starting Colts offense didn’t get much going in two series during Sunday’s preseason opener against the Broncos.

Their first crack at Arizona’s starting defense went much better.

Anthony Richardson marched Indianapolis 75 yards in six plays, opening the drive with an explosive quarterback run through the middle for 15 yards and ending it with a gorgeous touchdown pass of roughly 35 yards to Michael Pittman Jr., laying the ball into Pittman’s arms above and beyond two Arizona defensive backs.

“They’re in a cloud coverage, Pitt got around him, the safety was inside, and he laid it, it was perfect,” Indianapolis head coach Shane Steichen said. “Hit him in stride.”

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Jonathan Taylor followed Richardson’s drive-opening scamper with an 8-yard run of his own, juking and bouncing his way to get to the outside for a big gain. Richardson fired incomplete to Taylor on second-and-2, then laid a ball over Taylor’s head to the sideline on third down, picking up the first down and solid yardage.

A quick throw to Pittman then got the offense in position for the big strike.

“It was awesome,” Steichen said. “When you can score, go 75 yards in six plays like that, that’s what you want to be. You want to be explosive like that.”

The first-team offense largely got the upper hand on Arizona’s defense throughout the practice. Richardson completed 6 of 8 passes in 11-on-11, hitting Pittman twice, Taylor twice and two throws to Alec Pierce, including an in-rhythm strike to Pierce for 15 yards on the sideline.

Richardson was almost as good in 7-on-7 drills, completing 11 of 12 throws, including a deep ball to rookie Anthony Gould for a touchdown.

And Pittman was on fire throughout the practice. Pittman’s practice-ending touchdown came after he’d already produced two big plays in 1-on-1 drills, torching the Cardinals cornerbacks across from him for scores.

“AR was great today,” Pittman said. “From 1-on-1’s to that last one, we completed every go ball that he threw today between me and him.”

The Colts offensive line had a couple of early hiccups, allowing a couple of wins for the Arizona pass rush in one-on-one drills and one sack — Arizona’s Victor Dimukeje appeared to beat right tackle Braden Smith — but they settled into the practice as it progressed, repeatedly opening big holes for both Taylor and second-year back Evan Hull.

Two steps forward

The hamstring injury Trey Sermon suffered in the preseason opener against the Broncos opened an opportunity for Hull and Tyler Goodson, the two backs who’d previously been competing for the No. 3 role.

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Hull, a fifth-round pick in 2023 who ended up missing almost his entire rookie year due to a root tear of the MCL in his knee, made the most of his opportunities on Wednesday.

Handling most of the carries that would normally go to Sermon, Hull ripped off a handful of solid gains while working with both the first and second-team offensive lines.

He also flashed his receiving skills, catching one pass in 11-on-11 and four passes in 7-on-7 drills.

Flacco under fire

Veteran backup Joe Flacco didn’t get a chance to play with some of the receivers he’s liked most throughout training camp.

Ashton Dulin is out of the lineup with a hamstring injury, and Gould is playing more on the first team due to the absence of Josh Downs, who suffered a high ankle sprain last week.

Unlike the first-team offense, Flacco had some trouble with Arizona on Wednesday.

Flacco’s first throw was intercepted, a poor decision by the veteran, who rolled right, didn’t see any receivers come open downfield and tried to check it down to Hull too late, only to throw the ball into the waiting arms of Arizona linebacker Owen Pappoe.

The task didn’t get much easier. Flacco was “sacked” twice more, had a nice throw dropped by Tyrie Cleveland and lost his initial chance at a 75-yard drive when Pappoe ripped the ball out of tight end Drew Ogletree’s hands and then recovered the fumble he’d just forced.

Flacco ended up completing his final seven throws to finish a respectable 9 of 13, but most of those throws were short, and the second-team offense’s second chance at a score came up empty.

Injury report

The Colts got a handful of players back on the field. Defensive tackle DeForest Buckner (rest), cornerback JuJu Brents (shoulder) and rookie linebacker Jaylon Carlies (hip) were all back after missing varying lengths of time.

Sermon, Downs, Dulin, defensive end Titus Leo and linebacker Liam Armstrong did not practice. Downs was wearing a boot on his right ankle and using a rolling knee scooter.

Veteran defensive tackle Raekwon Davis remains on the non-football/illness list due to high blood pressure. The Colts are hoping Davis does not have to miss regular-season time.

“I hope not,” Steichen said. “He’s progressing well, so hopefully he’ll be out there sooner rather than later.”

Quick hitters

Steichen appeared to be frustrated with Arizona’s defenders tackling Indianapolis ball carriers to the ground a couple of times. The Colts lost Downs last week on a play where he was dragged to the ground. … Undrafted free agent Dalton Tucker, who has turned in a good camp and currently lines up as the second team’s right guard, gave up a “sack” of Flacco to Dante Stills. … Third-string quarterback Sam Ehlinger finished 3 of 4 in his 7-on-7 snaps, the only incompletion coming on a drop by Laquon Treadwell.

This article originally appeared on Indianapolis Star: Colts camp: Anthony Richardson, Michael Pittman Jr. torch Cardinals