Won a silver medal with Team USA at the Tokyo 2020 Olympic Games after leading the entire field in RBIs and home runs. He finished the tournament hitting .217 (5-for-23), with four runs scored, three home runs, and eight RBIs. He capped the scoring in the 8-1 victory over Israel with an RBI-single in the top of the ninth inning, hit a two-run bomb over the right field fence to give the U.S. a 2-1 lead over Korea in the Group B finale, and had a huge game against Japan in the quarterfinals going 2-for-4 with a double and a massive three-run home run over the left-field fence. Casas continued his power display with a two-run home run to centerfield in the first inning against the Dominican Republic (finishing 1-for-3 with two RBIs). He picked up a walk against Korea in the semifinals.

Casas was named to the All-Olympic Team (first base).

Casas started all four games at first base for Team USA at the WBSC Baseball Americas Qualifier, hitting .400 with three RBIs to help the U.S. secure the Olympic berth. He helped Team USA to a 7-1 victory over Nicaragua to open the AOQ, finishing 2-for-4. He notched his second consecutive two-hit game in Team USA’s 8-6 win over the Dominican Republic that clinched a spot in the AOQ Super Round for the U.S. He also delivered a key RBI double vs. Canada as part of a seven-run, eighth-inning rally in a 10-1 Super Round win. He finished the tournament with a 1-for-3 night vs. Venezuela in the clinching game – a 4-2 U.S. win.

Casas led the 2017 18U team in RBIs, driving in 13 runs while hitting .250 (8-for-32) en route to winning the WBSC U-18 Baseball World Cup in Thunder Bay, Ontario, Canada.

Casas finished with a .333 (8-for-24) average at the plate to go along with a team-leading 11 RBIs en route to a gold medal.

Hit .429 (12-for-28) and had 10 RBIs to help the team win gold in the COPABE Pan Am “AA” Championships.