The combination of national team calls-ups, suspensions and injuries subtracted five players from Sporting Kansas City’s lineup Thursday. Their successors — three of them just 20 years old — offered Sporting KC a glimpse of its future.

An optimistic start gave way to a dissatisfying conclusion.

Sporting KC pounced first yet settled for a 1-1 draw with the Philadelphia Union on Thursday at Children’s Mercy Park.

Forward Diego Rubio scored his first goal in 15 months to open the second half, but Philadelphia equalized 20 minutes later, evening a match that Sporting KC controlled in every statistic except the most important one.

“This is a game we should’ve had three points. We were the better team,” Sporting KC coach Peter Vermes said. “Whatever the statistics say, it doesn’t really matter — you can just watch the game and know that. But we had a five-minute lapse in the second half.”

Although Sporting KC (8-4-8) moved into first place in the Western Conference and extended its home unbeaten streak to 19 matches, it has played to back-to-back draws inside its home venue, which welcomed its 97th straight MLS sellout Thursday. It was in full control of the match after Rubio scored in the 49th minute, but that aforementioned lapse arrived soon thereafter.

Philadelphia drew even in the 69th minute on Roland Alberg’s penalty kick. The opportunity fell to Alberg after midfielder Benny Feilhaber was called for a foul on former Sporting KC forward C.J. Sapong in the penalty area.

“I think at best it’s a soft call,” Feilhaber said after watching the replay in the locker room, later adding, “It’s a penalty call that we haven’t gotten called for us over the 20 games or so in the season.”

It canceled the noteworthy score from Rubio, who was making his first MLS start in 12 months after an ACL injury shortened his 2016 season.

The comeback from the injury would feel complete with more significant impact in a match, Rubio said. And only five days ago, he offered a prognosis. “It’s coming,” he said.

Indeed. Rubio squeezed a ball between a pair of defenders and found the corner of the net in the 49th minute. He attempted a nearly identical shot in the first half but bent it just over the bar.

Rubio played 80 minutes before being replaced by Gerso Fernandes, who made a surprisingly prompt return after his shoulder popped out of place during Saturday’s match.

“Fantastic goal. I’m very happy for him and the fact that he was coming back from injury,” Vermes said of Rubio. “And the fact he was able to go 15 minutes longer than I thought he would have is a good sign as well.”

It just didn’t stand as the winner. Sporting KC finished with the advantage in the less critical numbers — shots (18-6), shots on goal (7-2), corner kicks (14-3) and possession (64 percent).

With a depleted lineup, at that. Three players in the starting lineup had not made an MLS start in a year. Rubio started for the first time since July 2016; homegrown defender Erik Palmer-Brown started for the first time since October 2015; and winger Daniel Salloi made his first career MLS start after scoring his first career goal off the bench last weekend. Salloi missed a prime chance in second-half added time that could have served as a game-winner. Ten feet in front of goal, he skidded his shot wide.

All three received praised after the game from Vermes.

“It was awesome,” said Palmer-Brown, a graduate of O’Hara High School. “Playing in front of those fans is unbelievable. It’s an amazing environment, and it’s really fun to be out there.”

The reason for the replacements’ presence: defenders Matt Besler and Graham Zusi and forward Dom Dwyer are with the United States men’s national team; midfielder Roger Espinoza served a one-game suspension for yellow card accumulation; and Fernandes was limited to the substitute role.

Sporting KC still pressured the Philadelphia defense often, though its final touch was lacking. Philadelphia keeper John McCarthy made six saves, a handful of them right at him.

“We could’ve scored three goals easily tonight, and we should’ve,” Vermes said. “Whether it’s young guys out there or not, we should’ve gotten three points. It’s not a night that we should’ve gotten (only) one. And I’m disappointed in that regard.”