Chargers hope losing close games doesn’t become contagious

An inability to win close games can be like a flu bug spreading through the locker room. The Chargers, their latest nausea-inducing last-second defeat coming in Sunday’s 19-17 loss to the Miami Dolphins, can only hope to contain it.

When kicker Younghoe Koo pushed a potential game-winning, 44-yard field-goal attempt wide right with five seconds left in StubHub Center, it dropped the Chargers to 1-10 in one-score games since the beginning of 2016 and 4-18 in such games since the start of 2015.

The Sept. 11 season opener at Denver ended in similar fashion, when Koo’s potential game-tying 44-yard field-goal attempt was blocked, and the Broncos held on for a 24-21 victory.

Asked whether a proliferation of narrow losses can pile up on a team mentally, veteran guard Matt Slauson said, “If you let it, sure, but it’s our job to not let it weigh on us emotionally. We have to be pros and learn from our mistakes and move on.”

Easy to say. Difficult to do, especially with the 2-0 Kansas City Chiefs coming to Carson on Sunday. The Chiefs whipped the defending Super Bowl-champion New England Patriots in their opener and beat Philadelphia 27-20 on Sunday.

“We always talk about the tightness, the toughness, the character of our group, and it’s times like these that it gets tested,” said quarterback Philip Rivers, who completed 31 of 39 passes for 331 yards and a touchdown against the Dolphins.

“We’ve got a division opponent coming here next week that is not going to have any sympathy for us losing two tough ones that went down to the buzzer. We can be sick about it for a little while, but we’d better get ready to go.”

Slauson stressed the need for the Chargers to have “perfect execution” at the end of the game, about “being our best at crunch time.” But the Chargers need to be better throughout, to capitalize on opportunities to bury an opponent.

They scored two touchdowns Sunday. They drove deep into Dolphins territory three other times but were unable to reach the end zone, settling for one field goal. The other two drives ended in a missed field-goal attempt and a punt.

On third and four from the Miami 23-yard line early in the second quarter, Rivers threw an incomplete pass between Keenan Allen and Antonio Gates, and Koo kicked a 41-yard field goal.

On a third-and-one from the Dolphins 17 just before halftime, the Chargers failed to chip blitzing safety Reshad Jones on the right side and Rivers was sacked by William Hayes for an eight-yard loss. Koo missed a 43-yard field-goal try.

A six-yard pass on third down from Rivers to Tyrell Williams would have given the Chargers a first down on the Miami 26 early in the fourth quarter. It was nullified by reserve tackle Chris Hairston’s holding penalty. Rivers’ long pass to Travis Benjamin was incomplete, and the Chargers punted.

“We moved the ball well; we didn’t turn it over,” Rivers said. “We’ve just got to finish some of those drives with touchdowns.”

Anthony Lynn, in his first year as Chargers coach, is aware of his team’s recent history but encouraged players not to succumb to it.

“We talked about that a little bit in our team meeting,” Lynn said Monday. “Some people say, ‘Same old Chargers.’ It’s not the same old Chargers. We lost a couple of close games. We have 14 games left. We’ll see at the end. … I started out 0-2 last year [as an assistant at Buffalo] and we won the next four games.”

Cool with Koo

Lynn said he has no plans to bring in a kicker this week to compete with Koo, the former Lou Groza Award finalist from Georgia Southern who has missed three of four field-goal attempts in two games.

“Koo’s our kicker,” Lynn said. “He competed well all training camp. He kicked well in Denver. He got one blocked. This is the first time he’s had a bad day. I told him you can have a bad play, but you just can’t have a bad day.”

A conversation with Koo on Monday helped Lynn retain his faith in the rookie.

“We just talked about his confidence and where he’s at, and I liked his response and the things he said,” Lynn said. “He’s very confident, and I have to give him the benefit of the doubt after being around him the whole offseason and watching how he competed and took that job. We’re hoping he’ll bounce back.”

Etc.

Through two games, the Chargers rank last in the AFC in yards rushing per game (54.0) and 15^th in third-down efficiency (25%, five for 20). … Lynn said he expects right tackle Joe Barksdale, who left Sunday’s game when he aggravated a left-foot injury in the third quarter, to play Sunday against the Chiefs. … Lynn on strong safety Jahleel Addae’s low hit on DeVante Parker, which upended the Dolphins receiver and sent him flying out of bounds before halftime, drawing the ire of several Miami players: “I can see why they were upset, but Jahleel was just playing hard. He’s not a dirty player.”

mike.digiovanna@latimes.com

Twitter: @MikeDiGiovanna