Vancouver’s Doneil Henry tangles with United’s Wayne Rooney during the first game at Audi Field, a 3-1 United win, on Saturday night. (John McDonnell/The Washington Post)

A single black, short-sleeved Wayne Rooney jersey hung on the side wall of Audi Field’s new D.C. United team shop Saturday night as a stream of soccer fans flooded the store, making a beeline to the array of carefully organized team apparel.

The No. 9 jersey was the last of its type available 20 minutes after the gates opened ahead of D.C. United’s inaugural match at its $400 million stadium in Southwest Washington. After careful consideration from multiple spectators, the jersey was quickly snagged by a dad and his young son before they both disappeared into the suffocating crowd.

The clamoring for Rooney’s jersey inside the team store was only the latest iteration of the frenzy that followed Rooney’s arrival in Washington in late June, and the English soccer star finally made his highly anticipated MLS debut Saturday night in D.C. United’s 3-1 win over the Vancouver Whitecaps.

“Of course it is a big night,” said Rooney, who entered the game in the 58th minute. “My debut in the MLS. My debut for D.C. United and a win, so I’m delighted. Fitness-wise felt okay. Thirty minutes. Obviously another tough week of training now.”

When United Coach Ben Olsen prepared to insert the heralded 32-year-old, Rooney jogged over from the corner of the field donning his lime green warmup bib, with the quiet “Rooney” chants getting louder as fans began to stand. They watched the star stand on the sideline at midfield before he ditched his warmup shirt and revealing his pristine No. 9 jersey.

Then “We want Rooney” chants began. The moment D.C. United fans had been waiting for had arrived.

“I was just as eager to go on the pitch as they were to see me on the pitch,” Rooney said.

As the public address announcer announced the substitution — Rooney in for forward Darren Mattocks — the noise from the crowd reached its peak.

“They got there. The energy got there,” Olsen said. “It took a couple goals to get the building rocking, but I think both the fans and even our team for the most part were a little nervy.

“I thought the second half was a lot of fun.”

Rooney agreed to a deal with United in late June, eventually inking a 2 1/2- year guaranteed contract worth about $13 million. Olsen said Rooney’s addition to the team has been “invaluable” and his knowledge and experience in the game helpful to the club’s younger players.

Rooney played the end of Saturday’s match as a striker, but Olsen said he believes Rooney is versatile and will be “fine” with whatever role he is asked to play for the remainder of the season.

“You saw what Wayne is: a high-quality elite soccer player,” Olsen said.

Rooney also was a big draw for United fans on the stadium’s opening night.

Before the 20,504 fans streamed into the venue, there was a scattering of Rooney jerseys on the backs of supporters, young and old.

For John Sadlik, a first-year D.C. United season ticket holder, he got his Rooney jersey hours before the match started, proudly proclaiming D.C. United’s time “starts now!” Don A. Bennett, a longtime D.C. United fan, donned a custom-made No. 9 black D.C. United jersey with the word “I believe” etched on the back.

Rooney showed flashes of what he brings to the club Saturday night, assisting on one of United’s two goals after he came on. Fans seemed glued to his every movement, and when the ball got even remotely close to him in the final 30-plus minutes, a slight murmur could be heard.

And as the final whistle blew, the match came to a close and the fireworks spewed out from atop the glowing video screen, Rooney lingered on the pitch, shaking hands with his opponents and celebrating with his teammates.

His first D.C. United match was in the books. Now for the next 2½ years.

“We are lucky to have him,” Olsen said.