Kenney played Magic: The Gathering competitively before transitioning to poker.[8] His first major live cash was in 2007 at the East Coast Poker Championships in Verona.[9]
In the 2010 WSOP, Kenney recorded his first major cash in the $25,000 No Limit Hold'em - Six Handed event, finishing 8th for $141,168.[10] He followed that up with a 28th place finish in the Main Event for $255,242.[11] In January 2011, he recorded his largest cash at the time with a 3rd place finish in the $100,000 No Limit Hold'em - Super High Roller Event at the PokerStars Caribbean Adventure for $643,000.[12]
Kenney won his first WSOP bracelet in 2014 after winning the $1,500 10-Game Mix Six Handed event, which earned him $153,220.[13] In January 2015, he earned $873,880 for a 3rd place finish in the $100,000 #1 No Limit Hold'em - Super High Roller 8 Handed Event at the PokerStars Caribbean Adventure.[14] In the 2015 WSOP, he had a runner-up finish in a $5,000 No Limit Hold'em event for $287,870.[15]
In 2016, Kenney defeated 2015 World Series of Poker Main Event champion, Joe McKeehen heads-up at the Pokerstars Caribbean Adventure $100,000 Super High Roller event winning $1,687,800.[16] Later that year, he won a $25,000 No Limit Hold'em HIgh Roller Event at the Aria High Holler 27 in Las Vegas for $422,400.[17] In the 2016 Super HIgh Roller Bowl in Las Vegas, he finished sixth for $800,000 in a No Limit Hold'em event.[18] In November 2016, at the Triton Poker Super High Rollers, he finished runner-up in the Main Event for $1,401,694 (HK$ 10,870,700).[19]
In January 2017, Kenney won the $50,000 No Limit Hold'em event at the PokerStars Championship Bahamas for $969,075.[20] In April, he won the € 100,000 No Limit Hold'em - Super High Roller Eight Max Event at the PokerStars Championship in Monte Carlo for €1,784,500.[21] At the 2017 Poker Masters in Las Vegas, Kenney won a $50,000 No Limit Hold'em event for $960,000.[22]
In March 2018, Kenney won $1,484,024 (HK$ 11,640,000) with a 5th place finish at the Super High Roller Bowl Event in Macau.[23] That same year, he joined the GGPoker team.[24] In January 2019, he won $914,616 with a victory in the No Limit Hold'em Main Event at the Aussie Millions Poker Championship in Melbourne.[25] At the 2019 Triton Poker Super High Roller Series in Montenegro, he recorded three consecutive seven-figure cashes with two victories and a runner-up finish totaling over $7,200,000.[26][27][28]
In August 2019, after placing 2nd to Aaron Zang in the £1,050,000 No-Limit Hold'em - Triton Million for Charity Event, Kenney received the largest single payout in live poker tournament history of £16,890,509 ($20,563,324).[29] The tournament had the largest scheduled single payout in poker tournament history with first place receiving £19,000,000 ($23,100,000). However, due to a prize splitting deal agreed with Zang, Kenney ended up receiving £16,890,509 ($20,563,324) for 2nd while Zang received the smaller prize of £13,779,491 ($16,775,820) for winning the tournament. The deal was made when the tournament entered heads up with Kenney holding an over 5:1 chip lead against Zang. Zang made a comeback and eventually won the tournament.[30][31]
In November 2021, Kenney finished runner-up in the $25,500 No Limit Hold'em - High Roller Event at the World Poker Tour Rock 'N' Roll Poker Open in Hollywood for $503,880.[32] In August 2023, at the Triton Poker Super High Roller Series in London, Kenney won the $250,000 Luxon Invitational for $6,860,000.[33]
Kenney is ranked 1st on the Hendon Mob All-Time Money List as of 2024.[34] As of 2024, his live tournament winnings exceed $71,000,000.[35]