The visitors are currently sixth in the table, two points behind fourth-placed Atletico Madrid, while Rayo Vallecano are eighth, boasting 23 points from their opening 15 matches of 2022-23.
Match preview
Rayo Vallecano finished 12th in La Liga last season on their return to the top level, and the capital outfit have again been impressive this term, boasting 23 points from 15 matches, which has left them in eighth position.
Los Franjirrojos have won six, drawn five and lost four of their 15 league games this term, and they are only four points off fourth-placed Atletico Madrid, which is an indication of how strong their start has been.
Andoni Iraola's side are unbeaten in their last seven league matches, recording three wins in the process, but they have drawn their last two against Celta Vigo and Girona.
Rayo Vallecano were also in Copa del Rey action on Tuesday evening, exiting the competition in the round of 32 courtesy of a 2-0 defeat to Sporting Gijon.
Los Vallecanos have been strong in front of their own fans in the league this season, picking up 14 points from seven matches, suffering just one defeat in the process.
Real Betis are actually unbeaten against Rayo Vallecano in La Liga since April 2014, although the points were shared in a 1-1 draw when the two sides locked horns for the corresponding match last term.
Manuel Pellegrini's side were also in Copa del Rey action during the week, booking their spot in the last-16 stage of the competition courtesy of a 4-1 victory over Ibiza Islas Pitiusas.
Real Betis have not triumphed in La Liga since the end of October, though, taking just two points from their last three matches against Sevilla, Valencia and Athletic Bilbao.
The Green and Whites finished fifth in La Liga last season, and they will certainly be eyeing another European finish this term, with the club currently sitting sixth in the table.
Real Betis have picked up 25 points from their 15 league matches this season, which has left them two points behind fourth-placed Atletico Madrid, while they have the third-best defensive record in Spain's top flight this season, conceding just 12 times.
Rayo Vallecano La Liga form:
D
W
W
W
D
D
Rayo Vallecano form (all competitions):
W
D
L
W
D
L
Real Betis La Liga form:
D
L
W
D
L
D
Real Betis form (all competitions):
L
L
W
D
D
W
Team News
Rayo Vallecano will again be missing Ruben de Tomas due to a tendon injury, but Salvi and Randy Nteka both made their returns in the Copa del Rey clash with Sporting Gijon on Tuesday.
The capital outfit will also be boosted by the returns of Oscar Valentin and Catena following suspensions, and the duo are expected to start on Sunday afternoon.
Head coach Iraola will make wholesale changes from the side that started in the cup, with Isi Palazon, Fran Garcia, Sergio Camello, Santi Comesana, Oscar Trejo and Ivan Balliu among those set to return.
As for Real Betis, Luiz Felipe is suspended following his red card against Athletic Bilbao on December 29, but Edgar Gonzalez is back from a ban of his own, so it should be a straight swap in the middle of the defence.
Youssouf Sabaly is out until next month with an ankle problem, while Paul Akouokou will again be missing for the Green and Whites due to a muscular problem.
There will be changes from the side that started in the Copa del Rey on Thursday, with William Carvalho, Luiz Henrique, Guido Rodriguez, Nabil Fekir, Alex Moreno, Borja Iglesias and Rui Silva all preparing to return.
Rayo Vallecano possible starting lineup:
Dimitrievski; Balliu, Catena, Lejeune, F Garcia; Comesana, Valentin; Palazon, Trejo, A Garcia; Camello
Real Betis possible starting lineup:
Silva; Ruibal, Ruiz, Gonzalez, Moreno; Rodriguez, Carvalho; Henrique, Fekir, Canales; Iglesias
We say: Rayo Vallecano 1-1 Real Betis
Rayo Vallecano have only lost once at home in the league this season, while Real Betis have won just two of their seven games on their travels, so it is not straightforward to pick an away victory here. The Green and Whites will believe that they have the players to collect all three points, but we have settled on a draw, as Rayo Vallecano will also bring a seven-game unbeaten run in La Liga into the contest.