Relegation was confirmed after last week's defeat at home to Hamilton, which meant that today's match was the first of two meaningless ties before the end of the 2018/19 campaign.
Kenny Miller netted the only goal of the game after being set up by fellow striker Andrew Nelson.
Miller's goal put him into the club's history books as our oldest ever goalscorer, at 39 years and 121 days, replacing Gordon Smith, who had previously held the record after he scored for the Dark Blues in a 2-0 win away to Falkirk in the penultimate match of the 1962-63 season. Smith was 38 at the time, but was just a few days away from his 39th birthday.
After the match, McIntyre praised Miller's goal, which ended the club's longest run of league defeats dating back to 1898-99.
Both teams went back and forth in a pulsating game which seen Dundee take the lead twice, only to fail to keep their lead for only a few minutes before Motherwell would draw level.
It would be the same story in the second half but it would be the Steelmen who would go ahead, only for the Dee to do the exact same as their hosts in the first half and level the scores right after.
The home side were reduced to ten-men with over half an hour still to play but Dundee could not take advantage of this scenario and would instead suffer heartbreak when Motherwell fired home the winner in the 94th minute to make it nine defeats In a row.
To make matters worse, around the same time, Hamilton and St Mirren both won a point in their matches with late equalisers to unofficially seal Dundee's return to the second tier.
Jim McIntyre, who is statistically Dundee's worst ever manager, called his teams defending as “criminal” and moaned that it was “ridiculous that we should have to score four goals to get a point” in another dour post-match interview