SANTA CLARA, Calif. – Michael Gallup saw the San Francisco 49ers’ safety playing in the middle of the field and knew Dak Prescott would look his way.

“One-on-one matchup,” the Dallas Cowboys’ rookie wide receiver said. “Hopefully he’s going to me.”

Gallup got off the line of scrimmage clean. Prescott was able to keep the safety in the middle of the field, knowing all the while he was going to Gallup on a go-route. The pass was perfect. Gallup ran by Jimmy Ward near the goal line and soon found his way in the end zone for a 30-yard touchdown.

Ultimately, the Cowboys lost to the Niners, 24-21, at Levi’s Stadium on Thursday, but a preseason result is meaningless. What matters is finding answers to questions that will come up in the regular season when the regulars play more than just a handful of plays.

For the Cowboys, one of their most pressing questions of the summer has been finding a way to make big plays in the passing game without Dez Bryant.

Through eight padded practices in Oxnard, California, the passing game struggled, especially getting the ball down the field.

Offensive coordinator Scott Linehan said the passing game was a work in progress last week. Prescott said he was still working on the chemistry with his wide receivers, which has been made a little more difficult because injuries to Allen Hurns (groin), Deonte Thompson (Achilles) and Terrance Williams (foot) have limited their practice time.

But on the 10th play of the only series the first-team offense would play, Prescott found Gallup to show what is possible.

Last year, Prescott had just two touchdown passes of 30 yards or more to wide receivers. Brice Butler had a 37-yarder against the Arizona Cardinals. Bryant had a 50-yarder against the New York Giants, but Bryant made most of that play by breaking a tackle after a short catch.

Prescott had just 14 completions of 30 yards or more to receivers last year.

Given the Cowboys’ offensive style will feature a heavy dose of Ezekiel Elliott running the ball, it is imperative they make plays over the top. If they can’t, then defenses can throw even more defenders into the box to stop the running game.

“It’s no secret 21 is going to get the ball,” right guard Zack Martin said. “Guys on the edge are going to have to make plays and we’ve got the guys to do it. It’s really good to see a young guy step up and make a big play like (Gallup) did with the first unit.”

Prescott completed all three of his passes for 39 yards in his 10 snaps. He found tight end Blake Jarwin for 3 yards and running back Rod Smith for 6 yards before finding Gallup. He also ran 12 yards to pick up a first down.

But the pass to Gallup was the highlight.

Sitting at his locker during organized team activities, Prescott pointed at Gallup as a highlight of the offseason work. After the offseason program ended, they spent time together at The Star, running routes. Gallup was also part of the group of receivers that went to Disney’s ESPN Wide World of Sports in Orlando, Florida, before training camp.

“If I’m not doing what I’m supposed to do, he’s going to let me know,” Gallup said. “It’s the quarterback’s way or the highway. That’s what it is. You got to be in the right spot at the right time and he’ll put it on you.”

The Cowboys have not asked Prescott to make many deep throws in his first two seasons. As a rookie, he worked underneath mostly with Cole Beasley and Jason Witten and relied on Elliott’s running. Last season, the passing game took a step backward with Prescott failing to throw for 200 yards in six of the final eight games.

But Jason Garrett said Prescott throws a good deep ball. What makes a good deep-ball thrower?

“The first thing is, you have to be a good decision-maker. There are opportunities to throw deep balls, you have to recognize when those are,” Garrett said. “You have to see the defense quickly and understand how your pattern overlays on the defense and how you want to attack them down the field. I think that’s where it starts.

"I think your feet have to be really good to get back and get the ball up. And then obviously just your touch and accuracy as a passer. I think there’s a misnomer that good deep ball throwers have to be guys with the strongest arms, that they throw it he farthest down the field. If you go back 100 years in football, nine routes, straight go-routes are completed 42 yards down the field. That’s typically where they’re completed.”

Thursday’s was just 30, but it was what the Cowboys needed.

“Coach tells us all the time you got to be able to win on nine routes,” Gallup said. “They’re going to load the box. We’ve got to have wide receivers that are productive. It’s what we’re trying to do.”