The Kansas City Chiefs received an almighty scare in the third quarter of their season-opener against the Baltimore Ravens at the GEHA Field in Arrowhead Stadium. Running back Isiah Pacheco seemingly suffered a gnarly injury that risked his participation for the rest of the night.Early in the second half, the third-year star looked winded as he rushed toward the Chiefs' sideline, collapsed to the floor and vomited. He was clearly feeling some discomfort and had his head on the ground as Kansas City's athletic trainers and medical staff tended to him, trying to diagnose what had gone wrong with their running back.However, minutes later, Pacheco sprung back up and returned to the game — much to the Chiefs sideline's relief. The 25-year-old's brief exit and battle with the mystery ailment went largely unnoticed given how quickly he got back.His return proved to be critical, as he helped the Chiefs extend their lead with a gritty play.Isiah Pacheco touchdown: RB gets in the endzone minutes after suffering a scary momentIsiah Pacheco returned to the field and his number was called upon on a 1st-and-goal play from the two-yard line. The running back tried to run the ball up the Ravens' gut but was immediately swarmed by a sea of defenders.He seemingly broke the plane but was pushed back nearly one yard. However, he refused to go down and the rest of his teammates joined the pile to shove their running back into the endzone.After a brief standoff at the edge of the goal line, a thud from Patrick Mahomes did the job, as Pacheco and a few others fell in the endzone for a Chiefs touchdown.It came at a critical juncture as the Ravens were down only three points, and a goal line stop would have likely left them down by one score. However, Pacheco's grit and the support from his teammates helped the home team take a 10-point lead and take control of proceedings.The running back's exit would have been a massive blow to the Chiefs' offense. He carried the ball on all but two of their rush attempts, and his exit from the contest would've left them with undrafted rookie Carson Steele as the lone threat in the ground game.Thankfully, Pacheco not only returned to the field after the scary incident but also helped his team score a critical touchdown.