The date was September 15, 2013.
Malcom Floyd was on fire in the first half, catching five passes for 102 yards against the Philadelphia Eagles. Then his season came to an end in a flash.
Hit over the middle, the reliable wideout was carted off the field and lost for the year.
When play resumed, an inexperienced, young 21-year old named Keenan Allen jogged in from the sideline for his very first offensive snap. Philip Rivers didn't hesitate to look his way, connecting for an 18-yard gain on 3rd-and-8 on his very next pass attempt.
"There was a flag, too," Allen was quick to remind. "Pass interference on my first play. Still made the catch on third down. I actually didn't know if I was going in. I was the fourth guy on the depth chart at best behind Vincent Brown and Eddie Royal. I thought (Wide Receivers Coach Fred) Graves was going to put Eddie in. But then he said I was going to go to the X full time and he was going to keep Eddie at the F. So I was ready. The rest is history."
For Rivers, it feels like it was only yesterday.
"Shoot, I remember him on one of his first few plays in there making a diving catch," the quarterback said. "That kind of got him going. He'd shown spurts, but that was the game for all of us where we were like, 'Ok, this guy's got something to him.' He had a couple other plays in the game, and that kind of kickstarted his entire career."
Allen impressed the Chargers with his cool, calm demeanor despite unexpectedly being thrust into the spotlight. He wasn't expected to see much action as a rookie with Floyd and Danario Alexander entering the season entrenched at the top of the depth chart. But after Alexander suffered a knee injury in training camp and Floyd out with a neck injury, Allen became the Bolts' go-to receiver.
He didn't disappoint.
Allen earned Pepsi Next Rookie of the Year honors, hauling in 71 catches for 1,046 yards and eight touchdowns. He followed that up with a solid sophomore year, catching 77 passes for 783 yards and four scores in 14 games.
Unfortunately, injuries plagued KA13 the next two seasons.
He got off to one of the best starts in NFL history, catching 67 passes for 725 yards and four TDs over the first eight games of the year before a freak kidney injury landed him on IR. Last year, he only played a half, catching six passes for 63 yards before tearing his ACL.
All eyes have been on Allen over the first three games of the 2017 campaign. Can he once again emerge as one of the league's premier wideouts, or will he struggle to reclaim his spot among the NFL's elite?
So far, the results have been overwhelmingly positive.
Allen has caught 19 passes for 196 yards and one TD over the first three games of the season. He is tied for ninth in the NFL in receptions, as well as targets per game (9.7).
Entering a critical Week 4 matchup with the Bolts desperate for a win, it's only fitting that KA13 faces off against the team in which he made his debut.
"We were just talking about that this past week that that was really when it started (for him), back in 2013," recalled Offensive Coordinator Ken Whisenhunt. "That's when Malcom got hurt and he went in and played. He made a catch in that game on a route that he had been awful at up until that point. That kind of turned the tide. You saw him grow up a lot. He's really worked hard at it. One of the things that I like and appreciate most about him is how hard he works at it. He loves the game. You see him on the practice field working that way. That's what you want to see from one of your best players."
However, Rivers recalls how the game came so easily to Allen as a rookie that it wasn't until his next year that he fully developed the habits that took his game to another level.
"Obviously he's super talented athletically as a player," Rivers said. "I think what was a challenge for him early was that he is obviously super, super smart, so he learned the offense very, very quickly. He could tell you what everybody's got on every route at all the different positions. So I think that came so easy for him that early on, he didn't have to go through that hard studying process of learning all the plays, and the ins and outs of the book. It came easy for him.
"Then, after that first year, all of a sudden the best corners from other teams are following him around. He had to really then not so much study what to do, but continue to work on his craft to get better and better as it gets more and more challenging to get open."
There's no doubt that Allen is a topflight wideout. Traditionally, elite receivers have been known to be prima donnas over the years. However, Allen couldn't be any more the opposite.
Outside of his "Slayer" moniker, he is as down to earth as they come.
Allen has matured from the raw 21-year old kid to the established wideout he is today. He is now a proud father of two and engaged to his longtime girlfriend. When not in the playbook, KA13 is taking care of his family.
"I'm a different guy now then I was then. I'm a father, first and foremost. I'm always in the house. I lay low and take care of them. I'm doing my job at home like on the field. But yea, I'm more (humble). We have so many weapons, I can't get the ball every play. I want to get the ball every play like those other receivers like Terrell Owens and (Chad) Ochocinco did, but I understand that's not always going to happen. I'm not that type of player to demand it. I can impact the game a lot of other ways like blocking. So just being out there, drawing coverages from other cornerbacks, whatever the case may be, I just want to be out there and help the team win."