Marco Arop OLY[citation needed] (born September 20, 1998) is a Canadian track and field athlete competing in the middle distance events.

He was offered a scholarship by Concordia University of Edmonton but switched his focus to track upon the recommendation of his high school basketball coach, Michael Wojcicki, who would later admit, "I had no idea that Marco was going to be this good.

"[6] Arop competed for Mississippi State in the 2018 NCAA Division I Outdoor Track and Field 800m in Eugene, Oregon, finishing in second place.

After the World Championships, Arop decided to end his amateur career and turn professional full-time, though the onset of the COVID-19 pandemic meant that the 2020 athletic season was largely cancelled.

He did not advance to the event final, a major disappointment that he and his coaches attributed to a longstanding habit of starting too quickly, resulting in fading toward the end of the race.

"[24] Shortly after his World Championship victory, Arop set a new personal best time of 1:43.24 at the 2023 Xiamen Diamond League event, where he finished narrowly second to Kenyan Emmanuel Wanyonyi.

[25] In the season-ending 2023 Diamond League Prefontaine Classic he finished second to Wanyonyi again, while setting a new Canadian national record and personal best time of 1:42.85.

[26] Arop began his 2024 season on 4 February, competing in the short track 1000m run at the New Balance Indoor Grand Prix in Boston, Massachusetts.

Arop won the event in a time of 2:14.74, breaking Nate Brannen's previous national record in the short track 1000m of 2:16.87 set back in 2014.

[30][31] On 8 September, at the Memorial Borisa Hanžekovića in Zagreb, Arop ran a new North American area record in the 1000 m, running 2:13.13 to become the fifth fastest man of all time at this distance.