Four years ago, Julian Champagnie ended his college career by scoring a game-high 23 points for St. John’s in a one-point loss to Villanova in the Big East tournament quarterfinals at Madison Square Garden. On Monday night, Champagnie will be back at MSG starting for the San Antonio Spurs in Game 3 of the NBA finals against the New York Knicks, his hometown team. It is unlikely outcome for a player who wasn’t selected in the 2022 draft and was once overshadowed by his twin, Justin, a guard with the Washington Wizards. Now, Champagnie is an important contributor on a team that trails the Knicks two games to none but looks like it should be in title contention for years to come. The Spurs hold a club option for Champagnie next year at $3 million, a bargain considering his production and young age. Champagnie turns 25 on June 29. San Antonio could pick up the option or negotiate a long-term extension, although those talks are likely on the back burner as the franchise focuses on how to succeed against the surging Knicks, winners of 13 consecutive games. In two games this series, Champagnie is averaging 12 points and seven rebounds, with all of his seven field goals coming on 3-pointers. But in both second halves, he hasn’t made a field goal, missing all five of his attempts in the opener and his only second half shot in Game 2. The Knicks overcame a 14-point third quarter deficit in Game 1, scoring the final 11 points to win 106-95. And in Game 2, the Spurs trailed by 14 midway through the fourth quarter, came back to go up by one point with just under a minute remaining but then lost 105-104 when star center Victor Wembanyama missed a jumper at the buzzer. If the Spurs are going to get back in the series, they need better late-game play from Champagnie, who remains a key figure in coach Mitch Johnson’s rotation. He has found security in the NBA even though he was never a sure-fire recruit out of high school or a top prospect out of college. Champagnie, who grew up in Brooklyn, N.Y. and played at Bishop Loughlin High School, became the first player from New York City to sign with Mike Anderson, who was named St. John’s head coach in 2019. He initially planned on heading to prep school, per the New York Post, but Anderson and his staff made Champagnie a priority, so he decided to enroll in college. At St. John’s, Champagnie started 81 of 88 games and averaged 16 points, 6.8 rebounds and 1.4 assists per game. He averaged more than 19 points per game as a sophomore and junior, making first team All Big East Conference each season even though the Red Storm finished fourth and seventh in the league those seasons. Despite having two seasons of college eligibility remaining, Champagnie declared for the draft. After not getting selected, he signed a two-way contract with the Philadelphia 76ers that July. On Valentine’s Day in 2023, the 76ers waived Champagnie, who only appeared in two games and didn’t have a point, assist or rebound. They wanted to make room for Mac McClung, who at the time had played in just two NBA games but who would represent the 76ers in the slam dunk contest that month, an event he ended up winning. Two days later, the Spurs claimed Champagnie off waivers, a move that set him on a much more lucrative path. As a rookie, Champagnie appeared in 15 games with the Spurs, averaging 11 points in just over 20 minutes per game. That July, Champagnie signed a four-year, $12 million contract, including $6 million guaranteed,