The hosts made an instant return to the top flight by finishing second last campaign, while their visitors finished sixth in the top flight to earn European football for the upcoming season.
Match preview
After a series of bounces between Spain's top two divisions in quick succession, Mallorca were relegated back down to the second tier in the 2019-20 season, finishing in 19th spot, four points adrift of safety.
For the second straight occasion, Los Bermellones won promotion back to the top flight at the first time of asking, finishing second with an impressive tally of 82 points.
Mallorca got off to a strong start, and would occupy a spot in the top three for almost the entirety of the campaign, not dropping out for any period of time after a victory over Malaga in late October.
A strong run to end the season, with four victories and two draws from the final six games, saw them finish comfortably in second place, nine points ahead of both third-placed Leganes and fourth-placed Almeria, while they were only pipped to top spot by Espanyol on goal difference.
They now head back into the top flight with momentum from a promotion-winning campaign, and Luis Garcia's men will be desperate to avoid the drop this time around.
Los Bermellones certainly do not have an easy start though, as they take on a Real Betis side who finished in sixth spot in the top flight last year.
Sunday's visitors had a fairly disappointing first half of the La Liga campaign last season, sitting in 12th spot in December and 10th place at the turn of the year.
However, Manuel Pellegrini's side kicked into gear in the final months, collecting 31 points from their final 16 league outings to quickly rise up the league, eventually finishing in sixth spot.
That place was sealed thanks to a victory over Celta Vigo on the final day, as Borja Iglesias, Nabil Fekir and Victor Ruiz got on the scoresheet to overturn a two-goal deficit and secure a 3-2 win.
As a result, they will make a return to the Europa League this season, presenting an exciting opportunity for Pellegrini's men while also bringing the challenge of a more packed schedule, meaning they will have to balance the squad throughout the campaign.
Given the upcoming challenge of regular midweek battles, Los Verdiblancos will be desperate to get off to a strong start to quickly establish themselves at the top end of the La Liga table before their competition begin to feel the benefit of longer rests between league clashes.
Mallorca form (all competitions):
Real Betis form (all competitions):
Team News
Mallorca midfielder Antonio Sanchez is ruled out of Saturday's clash, while Antonio Raillo, Angel Rodriguez and Amath Ndiaye are all doubts, and will likely be eased back into action further down the line.
New goalkeeper Dominik Greif has also been carrying a knock, but the former Slovan Bratislava man should be deemed fit to start between the sticks.
They have made further additions in the transfer market, with left-back Jaume Costa and loanees Takefusa Kubo and Rodrigo Battaglia all set to earn their first start for the club.
Real Betis come into the game without Diego Lainez and Youssouf Sabaly, with both players ruled out through injury.
Centre-back Marc Bartra and midfielder Victor Camarasa are both doubts, although the defender is expected to be the more likely of the two to start on Saturday.
Sergio Canales and Alex Moreno both recently recovered from injuries, and they are set to feature from the beginning.
French attacker Nabil Fekir should be a key man going forward, having hit 12 goals and 13 assists in 65 La Liga appearances in the two seasons since his arrival from Lyon.
Mallorca possible starting lineup:
Greif; Maffeo, Valjent, Sedlar, Costa; Battaglia, Babar, Galarreta; Rodriguez, Prats, Kubo
Real Betis possible starting lineup:
Silva; Montoya, Bartra, Ruiz, Moreno; Rodriguez, Canales; Rodri, Ruibal, Fekir; Iglesias
We say: Mallorca 0-2 Real Betis
Mallorca are faced with a particularly tough test upon their return to La Liga, and we see them falling short in the opening game to a strong Real Betis side.
The Sevilla-based side will go in search of another top-six finish this year, and will be keen to start on the front foot with three points.