The hosts, meanwhile, progressed into the last-16 of the US Open Cup with a topsy-turvy 4-3 win against Portland Timbers in midweek.
Match preview
After squeezing into the play-offs by finishing seventh in the Western Conference last season, Salt Lake decided to stick with head coach Pablo Mastroeni despite crashing out on penalties against Austin FC in the first round.
RSL looked set to march on after racing into an early 2-0 lead against their opponents, but Austin fought back and eventually equalised in injury-time before holding their nerve in the proceeding shoot-out.
This time around, Mastroeni's side appear to have a major fight on their hands to make it to the main event of the MLS event, although it is still an early stage of proceedings into the season.
However, 11 points from 10 games represents a disappointing beginning to the campaign, with successive 0-0 draws thwarting any upwards momentum in terms of climbing the table.
Mastroeni would have been delighted with his side's attacking verve and overall spirit to twice come from behind against Portland in the cup on Wednesday evening, though, and he will hope this serves his players well against the reigning champions on Sunday.
Indeed, despite only joining the MLS as an expansion team in 2018, Los Angeles scooped their maiden MLS Cup last season to cap a fantastic double alongside their second Supporters Shield triumph.
After dispatching their arch-rivals LA Galaxy 3-2 in the semi-finals before comfortably swatting Austin aside by three goals to nil, the manner in which Los Angeles forged history for themselves in the MLS Cup final will live long in the memory, with Gareth Bale scoring the latest goal in MLS Cup history in the 128th minute to make it 3-3 and force a penalty shoot-out.
Steve Cherundolo's side have picked up where they left off by claiming an impressive tally of 18 points from their opening nine matches, and they could move to the top of the Western Conference table should they manage to return from Salt Lake with all three points this weekend.
However, since beating LA Galaxy 3-2 yet again in mid-April, their form has become a little patchier with only one win from five games in all competitions. That said, despite conceding a last-minute equaliser against Monterey Bay FC in the US Open Cup on Wednesday, they held their nerve once again during the proceeding shoot-out to advance to the next round.
Real Salt Lake Major League Soccer form:
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Los Angeles FC Major League Soccer form:
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Los Angeles FC form (all competitions):
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Team News
Salt Lake appear likely to remain without Anderson Julio, Tomas Gomez, Bode Hidalgo, Jasper Loffelsend, Zack Farnsworth and Erik Holt through injury this weekend, with Mastroeni's options clearly limited as a result.
The 46-year-old used five players from his bench during the 4-3 victory against Portland in midweek, so he may feel confident of retaining the bulk of the starting XI that got the job done in such impressive fashion.
Los Angeles, meanwhile, will travel without Eldin Jakupovic, Antonio Leone and Maxime Crepeau, with the trio unlikely to return until later this month due to leg injuries.
Cherundolo made several changes in the cup in midweek, with captain Carlos Vela one of the most notable players rested, and the former Arsenal forward will almost certainly return to the starting line-up on Sunday.
Real Salt Lake possible starting lineup:
Beavers; Hidalgo, Glad, Pierre, Oviedo; Eneli, Ruiz, Chang; Gomez, Kreilach, Musovski
Los Angeles FC possible starting lineup:
McCarthy; Palencia, Maldonado, Long, Palacios; Tillman, Sanchez, Cifuentes; Bogusz, Vela, Bouanga
We say: Real Salt Lake 1-2 Los Angeles FC
Salt Lake will have taken plenty of confidence from their impressive fightback against Portland in the cup in midweek, but we still expect the visitors to have too much quality for them on Sunday.
Los Angeles will be keen to return to winning ways after looking a little shakier in their most recent matches, with Cherundolo's side firmly expected to make it to the business end of the MLS season once again later this calendar year.
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