Former Stanford starting quarterback K.J. Costello, who entered the transfer portal in December, announced Monday that he is heading to Mississippi State as a graduate transfer.Costello will be eligible to play his final college season in 2020 for new head coach Mike Leach, who departed Washington State in January after turning the Cougars into Division I’s top passing offense in four of the past six seasons.Costello, who visited the Washington Huskies last week, announced his decision on social media, tweeting, “Thank you Stanford. Dreams do become reality. Excited for what is next #HailState”Costello was a second-team All-Pac 12 selection in 2018, passing for 3,540 yards, with 29 touchdowns and 11 interceptions, while starting all 13 games. Appearing in only five games during an injury-riddled 2019 campaign, he managed only 1,038 passing yards with six touchdowns and three interceptions.