Chargers wide receiver Keenan Allen probably couldn’t believe he was about to have some good luck on the football field — the place where he lacerated his kidney in 2015 and where the ligaments in his knee exploded in 2016. Sunday in the Chargers’ final game of the season, the ball squirted out of Melvin Gordon’s hands right into Allen’s, and a path cleared for a 27-yard fumble recovery for a touchdown, the first points in the Chargers’ 30-10 win against the Raiders. “That was crazy,” Allen said. “I looked up and the ball was coming to me. I’ve never had a play like that.” It capped a season in which Allen made every kind of play imaginable for the Chargers. His 102 catches this season set a franchise record. His 1,393 yards receiving is the second most in team history. But a more important number for Allen was 16 — the number of games he played this year. Allen played the entire season for the first time in his career. Allen did so following a season in which he injured his knee in the Chargers’ first game of the 2016 season.