The Venezuelan struck in the 31st minute of Sunday's match against the Columbus Crew, taking advantage of a turnover near midfield.
Julian Gressel intercepted a wayward pass and fed Martinez, who cut the ball to his left foot and buried a shot inside the near post.
Martinez has tied a mark set by Roy Lassiter (1996), Chris Wondolowski (2012) and Bradley Wright-Phillips (2014), but has done so at an incredibly rapid rate.
The 25-year-old has reached the 27-goal mark in just 25 games. With nine games left after Sunday's match, Martinez appears set to shatter the mark.
Since joining Atlanta from Torino prior to the 2017 season Martinez has netted 46 goals in 45 games, maintaining a remarkable rate of more than one tally per game.
With his goal on Sunday Martinez also broke the MLS record for most goals in a two-season span, besting the previous mark of 45 set by David Villa in 2016 and 2017.
Additionally, Martinez has now scored in eight consecutive matches and is one game away from tying Diego Valeri's record of nine set in 2017.
Atlanta United would go on to win Sunday's match 3-1, with Martinez also providing a late assist to Miguel Almiron.