The opposing quarterback was making his second career start.
The Chargers were swelled with optimism after a 9-3 finish in 2017.
They were playing at home, even if StubHub Center isn’t the NFL’s most tilted venue.
The Chargers lost anyway, falling to Kansas City for the ninth consecutive time, 38-28, behind a blurring wide receiver, a whirling quarterback and an offense as precise and calculated as a decimal point.
“We definitely can beat those guys,” running back Melvin Gordon said. “We just made more mistakes today. We didn’t make our plays and we paid for it.”
The Chargers seemed to have so much leaning their way before kickoff, and that sensation continued … statistically.
They threw for more yards and ran for more yards, had more first downs and controlled the time of possession by nearly 10 minutes.
They had two 100-yard receivers, one 400-yard passer and 19 more snaps on offense.
That wasn’t enough.
What the Chargers didn’t have was Tyreek Hill, someone cornerback Casey Hayward last week called “the fastest guy in the league, hands down.”
The rest of StubHub Center was calling Hill that, too — after just the second time he touched the ball Sunday.
Trying to avoid a deflating start for the second consecutive season — the Chargers were 0-4 a week into October a year ago — the offense opened with a dud of a three-and-out.
Then the special teams made its 2018 debut by surrendering a 91-yard punt return for touchdown.
Hill took Drew Kaser’s kick just inside the 10-yard line, avoided Craig Mager, the first Charger to arrive, and then sprinted past all the others. A lunging Nick Dzubnar was the only one to really come close.
“We lost containment,” coach Anthony Lynn said. “We know he’s one of the fastest guys in the country and we lost containment.”
After the Chargers offense responded on its next possession to produce a 45-yard Caleb Sturgis field goal, the streaking Hill struck again, turning a quick pass from Patrick Mahomes over the middle into a 58-yard score.
Not 10 minutes into the game with the Chiefs having run five plays, the Chargers were losing on the scoreboard, 14-3, and in all three phases of football.
“It was a punch in the mouth,” defensive end Isaac Rochell said. “But we beating ourselves. We were making mistakes. It was us, not necessarily them dominating us.”
The Chargers would close the gap to 14-12 and trail 17-12 at halftime, rebounding against an opponent Lynn had welcomed as the perfect way to test his team’s development.
But Kansas City went 75 yards in 11 plays to start the third quarter, scoring on a shoveled one-yard pass from Mahomes to De’Anthony Thomas, and the Chargers would never get the deficit within one possession again.
As tests go, this was one the Chargers failed.
“A team like that, you can’t give them anything and you gotta take everything, and we didn’t do that,” Lynn said. “We give them too much, and they outplayed us.”
He was permitted to operate without sustained pressure and, when the Chargers did make him scramble, he did so with proficiency. Before the game was over, Mahomes completed another one-yard shovel pass for a touchdown. This one went to — of course — Hill, who capped his brilliant, three-score afternoon by back-flipping in the end zone.
“At times we put some pressure on him, but it wasn’t enough,” Lynn said. “And when we did, he moved around and made a play. Anytime you give him a chance to extend plays, he’s at home.”
Chargers receiver Keenan Allen can’t reach the ball, but, running back Austin Ekeler does, for a long first quarter gain against the Kansas City Chiefs at StubHub Center.(Robert Gauthier / Los Angeles Times)
Kansas City Chiefs defensive backs Orlando Scandrick (22) and Kendall Fuller (23) prevent Chargers receiver Keenan Allen from catching a fourth quarter pass from Philip Rivers at StubHub Center.(Robert Gauthier / Los Angeles Times)
Chargers running back Melvin Gordon slips past Kansas City Chiefs defenders during a fourth quarter drive at StubHub Center.(Robert Gauthier / Los Angeles Times)
Kansas City Chiefs quarterback Patrick Mahomes slips the tackle of Chargers cornerback Desmond King during fourth quarter action at StubHub Center.(Robert Gauthier / Los Angeles Times)
Chargers quarterback Philip Rivers slips past Kansas City Chiefs rushers, Allen Bailey, left, and Justin Houston, right, for a small fourth quarter gain at StubHub Center.(Robert Gauthier / Los Angeles Times)
Kansas City Chiefs receiver Tyreek Hill streaks past Chargers defenders for a 58-yard touchdown catch and run from quarterback Patrick Mahomes in the first quarter at StubHub Center.(Robert Gauthier / Los Angeles Times)
Kansas City Chiefs receiver De’Anthony Thomas is lifted up by a teammate after catching a thrid quarter, one-yard touchdown pass from quarterback Patrick Mahomes at StubHub Center.(Robert Gauthier / Los Angeles Times)
Chargers receiver Mike Williams fails to catch a touchdown pass from Philip Rivers in the fourth quarter against the Chiefs at StubHub Center.(Robert Gauthier / Los Angeles Times)
Chargers receiver Keenan Allen can’t pull in a pass from Philip Rivers as Chiefs corneback Stephen Nelson knocks it away during the second quarter.(Robert Gauthier / Los Angeles Times)
Philip Rivers finished 34 for 51 for 424 yards and three touchdowns, and Gordon and Keenan Allen both went over 100 yards receiving.
But the Chargers had the game’s only two turnovers, one of which was a fumbled punt return by JJ Jones to kill what had begun to resemble a potential fourth-quarter comeback.
And so another opportunity against Kansas City slipped through the Chargers’ fingers on a day when their multiple dropped passes included two that would have been touchdowns.
“You gotta move on to the next time,” defensive tackle Damion Square said. “With those guys, you know what’s coming. We just gotta stop ’em.”
Against the Chiefs, that remains the problem.