Former Cowboys 1st-round pick Marcus Spears is putting Dak Prescott ON BLAST over his quarantine party ... saying, "This was one of the most disrespectful things I've seen in a long time."
We broke the story ... Dak played host to a big gathering at his place in Prosper, Texas over the weekend -- and one witness says there were as many as 30 people in attendance at the height of the festivities.
Of course, this is a huge no-no ... as government officials have urged self-isolation amid the coronavirus pandemic -- and Spears ripped the Cowboys QB on Monday for putting the party on.
"This was one of the most disrespectful things I've seen in a long time."@mspears96 went OFF about hearing reports that police were called to investigate a potential party at Dak Prescott's house. pic.twitter.com/NsEUSQMLVS
"This is just dumb," Spears said on ESPN's 'Get Up.' "It's dumb and it's totally disrespectful with what we have going on right now in this country."
Spears says his gripe with Dak's get-together is simple -- if the virus spreads because of the party, it puts further unnecessary strain on medical personnel.
"The disrespect to do this and recognize that people that have to presumably take care of you after these dumb social gatherings that you should not be having, by the way, is the one that really irks me and rubs me the wrong way."
For his part, Dak has yet to publicly comment on the party -- which his teammate, Ezekiel Elliott, also attended.