Pat Mahomes debuts as Chiefs new starter by winning AFC's offensive player of Week 1 Vikings' Harrison Smith takes home NFC's Defensive Player of Week 1 By PRO FOOTBALL WEEKLY STAFFSept. 12, 2018 Patrick Mahomes tossed four touchdowns as the Kansas City Chiefs went on the road and upset the Los Angeles Chargers, an effort earning him the AFC's offensive player of Week 1.The flame-throwing Mahomes, in the second start of his career and first after the Chiefs dealt Alex Smith to Washington this offseason, completed 15-of-27 passes for 256 yards (9.5 YPA) and the four scores for a QB rating of 127.5. The Chiefs beat the Chargers, 38-28, an encouraging start following an offseason of significant change in Kansas City, none bigger than the decision to move on from Smith after his best season and hand the keys to the 10th overall pick in 2017.Meanwhile in the NFC, Ryan Fitzpatrick led the Bucs to the week's most stunning upset, a 48-40 road victory over the defending division champion Saints, in which he totaled 5 touchdowns and 453 yards (21-of-28 for 417 yards and 4 TDs through the air; 12-36-1 rushing) en route to taking home the conference's top offensive award in Week 1. In his first of (at least) three starts to begin the season in place of suspended Jameis Winston, the journeyman Fitzpatrick played the game of his life. The magic-making journeyman has delivered some big performances throughout his 14-year career, but this was completely unexpected with Fitzpatrick (5.9 career INT percentage) visiting a dangerous Saints 'D' that ranked third in that department last season.On the other side of the ball, Vikings All-Pro S Harrison Smith delivered a monster performance in his club's home win over the 49ers, collecting a eight tackles (2 TFL), one sack, one interception, and one fumble recovery, with the sack and pick of Garoppolo coming on the final two defensive series of a one-possession game.Pittsburgh's sophomore OLB T.J. Watt collected 11 tackles, four sacks, three QB hits and a blocked would-be game-winning overtime field goal in the 21-all tie in Cleveland. Watt, the little brother of J.J., has to be considered the more dominant player as the 2018 season gets underway.Jakeem Grant's 102-yard kickoff return touchdown, which proved to be the game-winner for the Dolphins over Tennessee, earned him top AFC special-teams honors in Week 1, while Greg Zuerlein, who authored a record breaking 2017 but missed the Rams' final three games with a back injury, earned NFC special teams player of Week 1. He converted all four of his three-pointers, including a 55-yarder, plus three extra pointers in the Rams' 33-13 triumph in Oakland.