Notre Dame football’s key offseason transfer portal addition on special teams only played one quarter in the Fighting Irish’s 49-7 victory over Stanford on Saturday. Afterward, head coach Marcus Freeman said graduate student kicker Mitch Jeter did not finish the game due to injury. “He’s had a tight groin,” Freeman told reporters in his postgame news conference. “I think on that kickoff, it didn’t feel great. They told me they were going to hold him. So, that’s all I know now.” Jeter’s final play was a 39-yard kickoff with 1:27 left in the first quarter. Before that, he had a successful PAT at…