Former Indianapolis Colts star Shaquille Leonard introduced himself to the team during his first training camp practice by intercepting Andrew Luck. It didn’t take the linebacker long to show the rest of the league he could change games, too. The three-time All-Pro and 2018 AP NFL Defensive Rookie of the Year will announce his formal retirement during a halftime ceremony Sunday, team officials said Wednesday. Leonard also will bang the team’s anvil before the Colts host the Las Vegas Raiders.