Summer League and D-League (2014–2015) After going undrafted in the
2014 NBA draft, Prather played for the
Atlanta Hawks in the
NBA Summer League and spent preseason with the
Phoenix Suns. He joined the
Bakersfield Jam of the
NBA Development League for the
2014–15 season. He helped the Jam win the inaugural NBA Development League Showcase Cup. On March 22, 2015, he scored a season-high 30 points in a 124–113 win over the
Rio Grande Valley Vipers. In 49 games, he averaged 12.0 points, 3.7 rebounds, 1.8 assists and 1.3 steals per game. Prather played for the NBA D-League Select Team in the
2015 NBA Summer League.
Perth Wildcats (2015–2017) 2015–16 season On July 25, 2015, Prather signed with the
Perth Wildcats for the
2015–16 NBL season. He was lured to Australia by former college teammate
Scottie Wilbekin. On November 22, he scored 26 points and made the winning free throw with 1.5 seconds left in the match to lift the Wildcats to a 91–90 win over the
Cairns Taipans. On January 15, 2016, he scored a season-high 27 points in a 95–68 win over the
Sydney Kings, helping the Wildcats snap a three-game losing streak. He helped the Wildcats reach the NBL Grand Final series, where they defeated the
New Zealand Breakers 2–1 to win the championship, with Prather scoring a team-high 19 points in game three. In 27 games, he averaged 16.3 points, 4.5 rebounds, 1.8 assists and 1.2 steals per game. He was subsequently named the Wildcats' Club MVP.
2016–17 season Following the 2015–16 season, Prather pledged to return to Perth for the
2016–17 NBL season. After a stint with the
Dallas Mavericks in the
2016 NBA Summer League, he re-signed with the Wildcats in July 2016. In the Wildcats' third game of the season on October 14, Prather scored 29 points in a 75–73 win over the New Zealand Breakers. On December 9, he scored a career-high 39 points in a 92–89 win over
Melbourne United. On February 10, 2017, he scored 29 points in a 101–74 win over the Sydney Kings. Two days later, he recorded 26 points and a career-high 11 assists in a 96–94 win over United. In the Wildcats' semifinal series against the
Cairns Taipans, Prather scored 22 points in game one and a game-high 24 points in game two to lead the Wildcats to a 2–0 sweep. In the NBL Grand Final series, Prather scored a game-high 22 points in game one; 18 points in game two; and 17 points in game three, as the Wildcats won their second straight championship with a 3–0 series sweep of the Illawarra Hawks. Prather was named in the
All-NBL First Team and finished second in NBL MVP voting (107 votes) behind
Jerome Randle (147) of the Adelaide 36ers. He was also named the club's most valuable player for the 2016–17 season to become the first-ever Wildcat to be the club's best in both seasons of a back-to-back championship era, and became the only player to be club MVP in more than one championship season. He also became the eighth Wildcat to win multiple club MVPs, the first player in history to take out the award in his first two years in the NBL, and just the second player to win club MVPs in his first two seasons with the club (the other being
James Crawford in 1987 and 1988). In 31 games, he averaged 19.5 points, 4.6 rebounds, 3.5 assists and 1.6 steals per game.
ratiopharm Ulm (2017) In April 2017, Prather joined
ratiopharm Ulm of the German
Basketball Bundesliga for the rest of the
2016–17 season. He helped the team reach the BBL semifinals. In 13 games, he averaged 8.5 points, 2.5 rebounds and 1.2 assists per game.
Melbourne United (2017–2018) The 2017 off-season saw Prather play for the
Cleveland Cavaliers in the
NBA Summer League. Believing he was on the verge of joining the Cavaliers for the season, Prather rejected an offer to return to the Perth Wildcats. After failing to secure an NBA contract, Prather briefly turned his attention to Europe, before instead deciding to return to Australia. Prather debuted for Melbourne in their season opener on October 5, 2017, scoring 20 points in a 99–97 win over the Adelaide 36ers. On October 28, he scored 30 points in an 87–85 loss to the
Brisbane Bullets. On December 16, he suffered a dislocated elbow in the second quarter of Melbourne's 84–78 win over the Illawarra Hawks. He subsequently missed the next eight weeks. He helped United win the minor premiership and reach the NBL Grand Final. In game two of the grand final series against the Adelaide 36ers, Prather had a game-high 20 points in a 110–95 loss. He scored 23 points in both games three and four. In game five, he recorded 19 points, 11 rebounds and five steals in a 100–82 win to help Melbourne clinch the championship with a 3–2 series victory. With the win, Prather collected his third NBL championship to become the first player in NBL history to win three straight titles in his first three seasons in the league. In 23 games for United in 2017–18, he averaged 16.7 points, 6.0 rebounds, 2.2 assists and 1.4 steals per game.
Promitheas Patras and BC Khimki (2018) On April 13, 2018, Prather signed with
Promitheas Patras of the
Greek Basket League. He appeared in the team's final four games of the regular season and then in all eight of their
playoff games, which included losing both the semifinals and the third-place series. In 12 games, he averaged 11.8 points, 2.3 rebounds, 1.2 assists and 1.0 steals per game. On July 24, 2018, Prather signed with Russian team
BC Khimki on a 1+1 contract. However, a clean-out of his knee resulted in his departure from Russia, as he was replaced on the roster by
Garlon Green in November and was unable to make his debut for Khimki.
Return to Melbourne (2019–2020) On July 17, 2019, Prather signed a two-year deal with Melbourne United, returning to the team for a second stint. However, due to another knee clean-out, he missed the first seven games of the
2019–20 season. He played in six of the next eight games before a right hamstring tear saw him miss the rest of the season from December 15 onwards. Melbourne went to lose to the Sydney Kings in the semifinals. On August 20, 2020, Prather parted ways with United after mutually agreeing to terminate the second season of his contract.
Hapoel Eilat (2020–2023) On August 23, 2020, Prather signed with
Hapoel Eilat of the
Israeli Basketball Premier League. He averaged 22.5 points (second in the league), 6.0 rebounds and 1.5 steals during the regular season. He had a 41-point game during the regular season and finished with a new club record of 631 points in total. He was subsequently named
Israeli League MVP for the
2020–21 season. He was also named to the
All-Israeli League Team. He helped Hapoel Eilat reach the semifinals, but sustained a knee injury during the dying seconds of the elimination match. He averaged 22.8 points and 5.8 rebounds in the playoffs. However, he missed both the 2021–22 and 2022–23 seasons due to back-to-back season-ending knee injuries, including a patella tendon injury and a fractured kneecap.
Brisbane Bullets and Shanxi Loongs (2023–2026) On December 21, 2023, Prather signed a two-year deal with the
Brisbane Bullets, returning to the Australian NBL for a fourth stint. On January 7, 2024, in his first game since June 2021, Prather scored eight points in 11 minutes in a 101–93 win over the
Sydney Kings. He averaged 6.7 points in seven games to finish the
2023–24 season. On April 10, 2024, Prather's contract for the
2024–25 NBL season was exercised by the Bullets. On December 24, he scored a game-high 36 points with seven 3-pointers in a 111–90 win over the
Adelaide 36ers. From round 10 onwards, he averaged over 25 points per game with 44 per cent shooting from 3-point range and seven rebounds per game. He finished as the third leading scorer in the competition with 21.3 points per game. He was subsequently named the Bullets Club MVP and earned
All-NBL Second Team honors. On February 7, 2025, Prather re-signed with the Bullets for the
2025–26 NBL season. In six CBA games, he averaged 9.3 points, 3.5 rebounds, 1.2 assists and 1.0 steals per game. On September 19, 2025, Prather scored a game-high 27 points in the Bullets' season-opening 104–95 win over the
New Zealand Breakers. On October 15, he recorded 34 points and 10 rebounds in a 110–93 win over the
Perth Wildcats. On November 12, he scored a game-high 26 points in a 113–84 loss to the Breakers, but injured his knee going up for a layup early in the fourth quarter. He was subsequently ruled out for the rest of the season after undergoing surgery to correct a hardware-related fixation issue. His season ended with him averaging a career-high 24.4 points per game. ==Personal life==