For Phoenix Rising, the U.S. Open Cup is an opportunity to grow. Should it be more?

The ball trickled out of bounds, three whistles blew and Juan Guerra walked toward midfield for a handshake. Satisfied, not jubilant.

“It’s a big weight off the shoulders of the players,” the Phoenix Rising manager would later say of his team’s 1-0 win over the Greenville Triumph.

From Guerra’s reaction, that much wouldn’t have been evident. Maybe it’s his relaxed demeanor — the coolness that enabled him to steady the ship when he was appointed amid turmoil last summer. Maybe, though, this is how Phoenix Rising views the U.S. Open Cup, the tournament in which advanced to the third round with Wednesday’s win.

Guerra’s lineup would suggest as much. He made eight changes from the team that drew San Diego Loyal, 2-2, in USL Championship play on Saturday. Seven of Rising’s 11 starters did not start any of their first three USL games of the season.

“It was a good opportunity to give minutes to players that we haven't seen with a lot of minutes before,” Guerra said.

Indeed, it was. For Rising to have the success it wants to have — expects to have — this season, it needs depth. Last year, a lack of trust in reserve players was a critical component in the most disappointing campaign in club history. One or two simultaneous injuries often derailed Rick Schantz’s squad.

Guerra wants to change that. On Wednesday, the results were positive. Although Carlos Harvey (one of the three repeat starters) scored Rising’s lone goal on a 21st-minute tap-in, it was the new introductions who starred. Baboucarr Njie was perpetually dangerous on the left wing and provided the assist on the winner. Eddie Munjoma created problems on the right, including the lone goal’s hockey assist. Goalkeeper Patrick Rakovsky made a highlight reel save in stoppage time, tipping a ferocious long-distance shot onto the crossbar and saving Rising from a stressful extra 30 minutes. Center back Mohamed Traore commanded the park, helping Phoenix to 68% possession.

“We're still developing, we're still transforming,” Guerra said. “We're still learning on how we want to do things in order to put together a team on the field that we could call the starting team. I don't think we're there yet.”

All that is good and important. And yet … the lineup changes still reveal a priority. Guerra could have rotated his squad on Saturday, or next Saturday against Birmingham Legion. Choosing, instead, to rotate in the Open Cup isn’t surprising for Phoenix. For years, through different coaching staffs, Rising has prioritized the league.

The question, then, is why. Last season, the USL’s Sacramento Republic reached the Open Cup final, selling out intense home games against MLS opposition. Union Omaha — a USL League One team — brought over 1,000 away fans to a cup quarterfinal against Sporting Kansas City.

Soccer fans in the U.S. often lament the lack of promotion and relegation. The fact that a club like Rising can’t dream of reaching the highest level of the sport in this country. But the Open Cup is the opportunity to make that happen. Saturday’s record crowd of 10,437 will likely only be matched in the playoffs — unless an MLS team comes to East Washington Street. Imagine LA Galaxy, with players like Chicharito and Riqui Puig, playing in front of a singing, dancing south end full of rabid Rising supporters. Those are the moments that make soccer unique.

More: 'We were promised a little bit more': New Rising stadium draws mixed reviews

Maybe, if Rising continues to advance, they’ll change their priorities. After Wednesday’s game, Guerra was asked as much. He responded only with platitudes.

“Every game we play is the main focus for us,” Guerra said. “I'm not gonna choose regular season or Open Cup.”

With his actions, he did. It was enough to beat a USL League One team, just as it was enough for Rising to reach the fourth round last year. But in each of the last six editions, Rising has been eliminated by a team at the USL level or below.

Which raises the question: Why not dream?

This article originally appeared on Arizona Republic: Phoenix Rising advances in U.S. Open Cup. Why not dream big?