After transitioning into kickboxing, Verhoeven began training at the age of seven and started competing against adults when he was 16 years old, due to his large size.

[2] He has trained mainly in Zevenbergen under Dennis Krauweel at Superpro Sportcenter, with fellow kickboxers Benjamin Adegbuyi, Albert Kraus and Alviar Lima.

As he was leading the judges' scorecards after the first two, two-minute rounds, he advanced to the quarter-finals where he lost out to the eventual tournament winner, his countryman Semmy Schilt by the same margin.

[16][17][18] He caused a major upset to win the Glory 11: Chicago - Heavyweight World Championship Tournament in Hoffman Estates, Illinois, United States in October 2013.

[25][26][27][28] Verhoeven was scheduled to make his professional boxing debut against Nikolaj Falin at Mix Fight Gala XV in Darmstadt, Germany on 26 April 2014[29] but his opponent was changed to János Finfera for undisclosed reasons.

The fight ended in a technical knockout, as Zimmerman injured his left knee, following a missed spinning back kick.

[38][39] For his second title defense, Verhoeven was scheduled to fight the former SUPERKOMBAT Heavyweight GP winner Benjamin Adegbuyi at Glory 22: Lille.

[47] Verhoeven was scheduled to defend his title for the fourth time just three months later, at Glory 28: Paris, against the newly crowned FFC Heavyweight champion Mladen Brestovac.

[53] Intending to keep his promise, Hari came out aggressively in the first round, opening a cut on Verhoeven's nose early in the fight.

[58] Glory would once again book Verhoeven in a non-title match against Antônio Silva, in what the website Bloody Elbow called a "gross mismatch".

[65][66] He was scheduled to defend his title for a record setting eighth time at Glory 59: Amsterdam, when he faced the WGP Heavyweight champion Guto Inocente.

[67] Inocente would use several illegal moves during the fight, such as a foot sweep and a judo throw, however, Verhoeven would again dominate the bout, winning all five rounds on each of the judges scorecards.

Since their first fight, Hari had served a prison sentence, and had only fought once in the meantime, he won against Hesdy Gerges by unanimous decision but later turned into a no-contest.

[74] It was revealed by Glory in October 2020 that Verhoeven would fight a trilogy match with Jamal Ben Saddik in early 2021, although the exact date and event weren't announced.

[81] It was announced on August 23, 2021 that Verhoeven would make the tenth defense of his Glory Heavyweight Championship against the 2010 K-1 World Grand Prix winner Alistair Overeem.

[84] On April 12, 2022, it was announced that Verhoeeven's next fight would take place at the inaugural "HIT IT" event, a sports and live entertainment show.

[85] Although it was initially assumed that the fight would be an exhibition bout, on June 2 it was revealed that he would face the former It's Showtime World Heavyweight champion Hesdy Gerges for the fourth time in his professional career and who he had beaten in all three of their previous meetings.

The title bout was initially supposed to take place in spring 2023, but was postponed after Verhoeven suffered a knee injury in training.

He also worked closely with WBC and Lineal heavyweight world champion Tyson Fury, whom he credits with turning his jab into the highly effective weapon it is now.

[116][117][118] Verhoeven made his film debut in a small role opposite Alain Moussi in the sequel Kickboxer: Retaliation.

[119] In 2022, the four-part docu-series RICO: Dream Big followed Verhoeven in the run-up to his fight against Badr Hari and his attempts to break through in Hollywood.