American sprinter Justin Gatlin says he is perplexed by the London crowd’s reaction to his unexpected victory over fan-favorite Usain Bolt in the men’s 100-meter final at the IAAF World Championships on Saturday.

Justin Gatlin 100m IAAF World Championships news

Gatlin — who previously won gold in the 100m at the Helsinki World Championships in 2005 — finished the race in a season-best 9.92 seconds to beat Bolt by 0.03 seconds and was heavily booed by the crowd at London’s Olympic Stadium.

Before Saturday, Bolt — who won three gold medals at the 2016 Rio Olympics — had been the world record holder for both the 100m and 200m competitions, and was set to retire following this year’s IAAF World Championships. However, the eight-time gold medallist from Jamaica — who will be 31 later this month, finished bronze on Saturday in his final individual race.

Gatlin, 35, is one of the most notorious cheaters in the sport of sprinting. The Brooklyn native — who won gold in the 100m at the 2004 Athens Olympics — has been suspended twice for doping violations. On Saturday, Gatlin was jeered every time he was introduced before the 100m heats, semifinals and final. The loudest boos and taunts, however, came after he defeated Bolt, though they subsided somewhat when Gatlin stepped up to the podium to receive his medal.

The American was banned for two years in 2001 while he was at college, and also served 12 months of his sentence for consuming a prohibited amphetamine after successfully arguing he had taken the drug as medication for attention deficit disorder.

Gatlin was also banned in 2006 for eight years, a suspension which was later shortened to four following an appeal, for testing positive for the prohibited steroid testosterone.

When asked about his opinion on the crowd’s reaction to his victory, Gatlin told CNN: “It leaves me scratching my head,” he said. “I’ve been back in the sport since 2010. I wasn’t booed in 2012, ’11, ’12 — which was still in London — ’13 or ’14 or ’15 and not that much in ’16.”

The third-place winner of the 100m race at the London 2012 Olympics also criticized the media for inflating his rivalry with Bolt, whom he said he admires and has a great relationship with.

Bolt will still attempt to win gold at the men’s 4x100m relay in London this year.

Nine of the 30 fastest 100m times, including the top four, have been set by Bolt. The other 21 times on that list belong to athletes who have, at one point, violated doping regulations.

In 2015, Gatlin also faced off against Bolt at the World Championships in Beijing for his first race after returning from his eight-year ban. The American had boasted a 28-race undefeated streak up until then and seemed likely to beat Bolt as the world-record-holder. Bolt ultimately won by 0.01 seconds.

Usain Bolt ran his fastest time of the season to win his Olympic 200-meter semi-final in 19.78 seconds in Rio on Wednesday as his American rival Justin Gatlin missed out on a spot in the final.

Usain Bolt Continues Hot Olympic Streak With 200M Semifinal Win; USA’s Justin Gatlin Crashes Out

The Jamaican won the 100m on Sunday night and is now seeking an eighth Olympic gold medal by retaining his 200m title.

Gatlin, 34, won silver behind Bolt in the 100m final, but only finished third in his semi-final.

Great Britain’s Adam Gemili, 22, reached Thursday’s final as one of two fastest losers.

Gatlin, banned twice for doping violations, clocked 20.13 and failed to advance along with another favorite: Jamaican Yohan Blake. 

Blake, who won silver behind Bolt in London in 2012, has been hampered by injury over the past few years and faded to finish sixth with a time of 20.37 seconds.

American LaShawn Merritt, who has run 19.74 this year, is likely to pose the biggest challenge to Bolt in the final.

But Bolt believes he can break his world record of 19.19 and could even go under 19 seconds in the final.

“I definitely think I can try for the world record, I definitely feel that,” Bolt said. “I need to run efficiently and get into the straight and run the perfect race.”

Nonetheless, the Jamaican added that he believes he would have a better chance of achieving his goal to run under 19 seconds if he gets a high lane, adding: “If I get a lower lane it’s always harder for me to run the corner when it is tighter.”

On Wednesday night, the Jamaican felt someone on his right side challenging him the last few meters of the race. After quickly glancing sideways, Bolt saw that it was Canadian Andre De Grasse, who won bronze in the 100m, and De Grasse was threatening to pass him.

However, Bolt flashed a big smile, accelerated and beat the Canadian at the finish line. Once there, he turned and wagged a finger De Grasse’s way, as if to say, “Not yet.”

Afterwards, the two embraced, laughed together and walked back to the locker room side-by-side, displaying no hard feelings.

“I don’t think he expected me to do that,” the 21-year-old De Grasse told reporters after the race. “I had to push him a little bit, you know, see what he has left in the tank.”

Bolt, who turns 30 on Sunday, said: “He was supposed to slow down. I said: ‘What are you doing? It’s a semifinal.’ But I think he wanted to push me.”

On Gatlin’s exit from the competition, Bolt told BBC Radio 5 live: “Everybody’s in shock. You can tell from the 100m he’s getting old. It’s a fact the older you get, the rougher it gets to double.

“Next year if I go to the World Championships [in London] I’m not going to double. I’m going to do the 100m and that is it.”

RIO DE JANEIRO, BRAZIL – AUGUST 17: Usain Bolt of Jamaica looks on prior to the Men’s 200m Semifinals on Day 12 of the Rio 2016 Olympic Games at the Olympic Stadium on August 17, 2016 in Rio de Janeiro, Brazil. (Photo by Cameron Spencer/Getty Images)