Outspoken UFC star Colby Covington hit out at "all the slime in Hollywood" as he took aim at those he claims have wished harm on United States president Donald Trump.

Trump was this week taken into hospital after contracting coronavirus, with the 74-year-old later declaring on Saturday night that he is "feeling much better" and hoping to be "back soon".

Covington is a well-known supporter of the president and took a personal call from Trump after defeating Tyron Woodley in his latest fight last month.

The 32-year-old was in attendance for the first presidential debate between Trump and election rival Joe Biden in Cleveland last Tuesday and told his fans he has since tested negative for COVID-19.

In the same update, posted on Instagram, Covington took the opportunity to take a swipe at Trump's detractors.

"For the people who constantly slander my name, but are all of a sudden concerned with my health and well being: I'm COVID free," Covington wrote.

"I've been tested 7 times in the past 3 weeks, including prior to and after meeting with the POTUS. I was also tested during fight week, as well as before and after the debate. ALL NEGATIVE.

"Speaking of ALL NEGATIVE, how about all the slime in Hollywood and woke sports wishing harm on a 74 year old grandfather!?! How tolerant!

"Unfortunately for them and fortunately for America, @realdonaldtrump is a fighter!!! He KO's the fake news media daily. He KO'd Slow Joe and Chris Wallace at the same time on Tuesday! Now it's time for a casual weekend KO of COVID! Here's to a speedy recovery and 4 MORE YEARS!!!"

For the people who constantly slander my name, but are all of a sudden concerned with my health and well being: I’m COVID free. I’ve been tested 7 times in the past 3 weeks, including prior to and after meeting with the POTUS. I was also tested during fight week, as well as before and after the debate. ALL NEGATIVE. Speaking of ALL NEGATIVE, how about all the slime in Hollywood and woke sports wishing harm on a 74 year old grandfather!?! How tolerant! Unfortunately for them and fortunately for America, @realdonaldtrump is a fighter!!! He KO’s the fake news media daily. He KO’d Slow Joe and Chris Wallace at the same time on Tuesday! Now it’s time for a casual weekend KO of COVID! Here’s to a speedy recovery and 4 MORE YEARS!!! #MAGA #Trump2020 #KeepAmericaGreat #AmericasChamp #DragonEnergy

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