Late in the third quarter, as the Washington Football Team cruised downfield, FedEx Field became a portal to the past. Here was quarterback Taylor Heinicke, again replacing an injured veteran, again sparking a struggling unit, again pushing to complete a comeback — just as he had eight months ago in a first-round loss to the Tampa Bay Buccaneers.

This time, his off-script, energy-shot style of play appeared on first and 20. He stepped up in the pocket, drew a linebacker to him and got off a two-handed chest pass that might’ve looked more natural on a basketball court. He turned what might’ve been a sack into a 17-yard gain and a manageable second down. The fans, back in the stands in full for the first time since 2019, deprived of exciting quarterback play for much of the past decade, expressed their appreciation.

“HEIN-ICK-E!” they chanted. “HEIN-ICK-E! HEIN-ICK-E!”

The drive, like the game, didn’t end as Washington wanted. Dustin Hopkins missed a 51-yard field goal attempt, and Washington lost the season opener, 20-16, to the Los Angeles Chargers. But Heinicke looked polished, converting 11 of 15 passes for 122 yards and a touchdown, adding 17 rushing yards. Coach Ron Rivera said Sunday if the hip injury suffered by Ryan Fitzpatrick is serious — he will miss at least three weeks with a hip subluxation, and Heinicke was named the starter Monday — he would have full confidence sticking with Heinicke against the New York Giants on Thursday night.

“When Taylor stepped in and brought some energy,” Rivera said Sunday, “I thought that was a huge plus.”

While it’s risky to put too much stock in the performance — Heinicke attempted 15 passes against a defense that hadn’t prepared for him — he appeared impressive. He made decisive reads. He spread the ball around. He pushed downfield when possible and scrambled when necessary. Each of his three full second-half drives lasted at least eight plays — barring the one-play opportunity halted by a game-turning Antonio Gibson fumble — traveled at least 35 yards and finished in Chargers territory.

“The biggest thing is going out there with some confidence,” Heinicke said. “I go out there and kind of play freely, just knowing what we’re trying to accomplish. I felt like we were doing pretty good but just came up a little short.”

Heinicke, last year’s “quarantine” quarterback who was signed away from studying mathematics, can extend plays with his feet, and though he seemed more conservative scrambling Sunday than he was in January, the value of his mobility was apparent. He minimized mistakes — the chest pass erased right guard Brandon Scherff’s 10-yard holding penalty from the play before — and created explosive opportunities, such as a preposterous 34-yard catch by Terry McLaurin.

“I didn’t really get to see it clearly,” Heinicke said of McLaurin’s highlight grab. “I believe I was on the ground at that point.”

The three full possessions Heinicke played in the second half could provide a snapshot of what the offense might look like moving forward. There is likely to be a lot of the same foundation — Heinicke has spent the better part of six years around offensive coordinator Scott Turner — but with a better chance to turn broken plays into big gains.

The first drive highlighted Heinicke’s throwing ability as he completed all five passes, including an 11-yard touchdown toss to tight end Logan Thomas. The second showed an offense better equipped to support the quarterback as Gibson, who has become a more complete running back in his second season, rushed seven times for 30 yards. The third illustrated the options available when the unit can run and pass, and how Heinicke can use his mobility to keep it on schedule, though the drive still sputtered because of a 15-yard clipping penalty.

So while Washington totaled just 10 points with Heinicke — a roughing-the-passer penalty led to a field goal just before halftime — the offense appeared capable of more. If only the vaunted defense had prevented a few more third-down conversions, or if Gibson hadn’t fumbled near Washington’s goal line, or …

“We shot ourselves in the foot a couple times,” Heinicke said. “But we have a short week against a division opponent on Thursday, so we’ll have a short mind-set.”

Since his playoff performance, many teammates have expressed belief in Heinicke. McLaurin, Thomas and others praised his poise and heart. Even though cornerback William Jackson III, a free agent signing, wasn’t here then, he noticed the way the sideline and the stadium grew energetic for the backup.

“[Heinicke] came in [and] did great,” he said. “He’s a gamer, and he did good. He did well enough for us to win the game.”

“We got supreme confidence in him,” Thomas added. “Taylor’s a baller, man.”

This game was another flash in a career built on them. Heinicke has been behind the scenes since going undrafted in 2015, only stepping up when others are hurt, and even when he stated his strongest case for a larger role in January, Washington decided it hadn’t seen enough to go all-in.

Heinicke has lived for and through these moments for six years, sparks that have never been sustained. But now, because of the schedule and because of Fitzpatrick’s injury, he gets another shot to prove he’s ready to be a frontman.