The visitors are currently 11th in the Major League Soccer Eastern Conference, and head into this one on the back of a 4-1 loss.
Match preview
Portland Timbers still have it all to play for right now when it comes to securing a playoff position at the end of this campaign, and while they currently occupy one of those slots, it is incredibly tight.
Giovanni Savarese's squad are just one point ahead of their nearest challengers, Los Angeles Galaxy, therefore there is real pressure on Sunday's match.
The Timbers come into this game on the back of two consecutive victories which will have added plenty of confidence to the squad as they defeated Seattle Sounders and Austin FC.
Both of those matches finished 2-1, and while they might have won those, the tightness of each fixture is something that they will no doubt want to try and avoid.
The goals came from defenders last weekend as Bill Tuiloma and Zac McGraw got themselves on the scoresheet, showcasing that Portland have attacking qualities from all across the field.
The visitors have not been quite as consistent in recent weeks, and that has been the story of their season, which is why they are currently in 11th place.
Last weekend saw the squad put together a brilliant 3-2 victory against DC United, with a trio of second-half goals ensuring that they took all three points.
However, Atlanta United were not able to follow up on that result in midweek when they were comfortably beaten 4-1 by Philadelphia Union.
Andrew Gutman had drawn his team level in the 24th minute, but the Five Stripes were unable to hold onto that result, and the game quickly ended up running away from them.
Only two teams in the Eastern Conference have conceded more goals than Atlanta United this season, and that is something they must be wary of heading into this weekend.
Portland Timbers Major League Soccer form:
Atlanta United Major League Soccer form:
Team News
Felipe Mora is someone that the Timbers are having to cope without at this stage of the season due to a recent knee surgery, and that will be the case once again this weekend.
The exact same back four is likely to be used on Sunday, especially since both of Portland's goals against Austin came from players in those positions.
Meanwhile, Diego Gutierrez is a player that could potentially be able to make his way into the matchday squad as he nears his return from a foot injury.
The visitors will once again be without the services of Brad Guzan and Miles Robinson due to knee injuries.
Josef Martinez could end up being preferred to Ronaldo Cisneros as Atlanta United search for more firepower upfront after their recent defeat.
Portland Timbers possible starting lineup:
Ivacic; Tuiloma, McGraw, Zuparic, Bravo; Williamson, Chara; Blanco, Y. Chara, Moreno; Asprilla
Atlanta United possible starting lineup:
Rios; Sanchez, Franco, Gutman; Lennon, Araujo, Sosa, Almada, Wiley; Sejdic, Martinez
We say: Portland Timbers 2-0 Atlanta United
Portland Timbers have got a lot more to play for in this particular game when it comes to what the points could mean, and that should be enough to motivate them to a victory.
The hosts have the stronger of the two squads, and their form throughout the season would suggest they are capable of defeating Atlanta United comfortably.