After going un-drafted in the
2011 NBA draft, Allen moved to France and played for
Olympique Antibes during the 2011–12
LNB Pro B season. In 32 games for Antibes, he averaged 13.5 points, 8.2 rebounds, 1.3 assists and 1.8 steals per game. In 2012, Allen began a successful career playing in Israel, signing with
Hapoel Tel Aviv for the 2012–13 season. After an injury hit year in 2012–13, Allen moved clubs and joined
Hapoel Afula for the 2013–14 season. In 34 games for Afula, he averaged 19.5 points, 13.1 rebounds, 1.9 assists, 2.3 steals and 1.6 blocks per game. On July 22, 2014, Allen signed a two-year deal with
Maccabi Haifa. However, his stint with Haifa only lasted half a season after being released by the club on December 7, 2014. In 20 league games for Šiauliai, he averaged 5.2 points and 6.2 rebounds per game. On September 24, 2015, Allen signed a short-term contract with Hapoel Tel Aviv, returning to the club for a second stint. On September 1, 2016, Allen signed with Israeli club
Hapoel Be'er Sheva of the
Liga Leumit. On September 10, 2017, Allen returned to Hapoel Tel Aviv for the 2017–18 season. However, on December 9, 2017, Allen was released by Hapoel after appearing in eight games. On January 11, 2018, Allen returned for a second stint in
Hapoel Afula for the rest of the season, joining his former teammate
Tre Simmons. On August 1, 2018, Allen signed a one-year deal with
Peristeri in Greece. However, on October 21, 2018, Allen parted ways with Peristeri and joined
Hapoel Haifa. On August 30, 2020, Allen signed with
Apollon Limassol in the
Cypriot League. On February 2, 2021, Allen signed with
Kaposvari KK of the Hungarian
Nemzeti Bajnokság I/A (NB I/A). He averaged 18.7 points, 8.5 rebounds, 1.7 assists and 1.8 steals per game. On August 23, 2021, Allen signed with
Cañeros del Este of the Dominican
Liga Nacional de Baloncesto. ==The Basketball Tournament (TBT)==