EAST LANSING, Mich.—Tyson Walker may not be the leading scorer every game, but he’s a key ingredient that has No. 19 Michigan State off to its best start in four seasons. “Tyson, the guy that stirs the drink usually gets the team going,” Michigan State coach Tom Izzo said after the Spartans’ 80–64 win Saturday over Penn State. “He’s doing that now, and it’s been fun to watch.” Walker, who transferred from Northeastern to Michigan State during the offseason, finished with 10 points and nine assists. He was instrumental in helping the Spartans mount a 31–3 advantage in fastbreak point, pushing the ball to Gabe Brown, who led the team with 15 points, and Marcus Bingham Jr., who had 12. “I started to get the rhythm of it the last two weeks of just get going,” Walker said about running the fastbreak. “It’s fun now.” The Spartans (9–2) have won …