The visitors have struggled this season, only picking up nine points from their opening 15 matches, which has left them in 18th spot in the table, while Rayo are 11th on 19 points.
Rayo have won four, drawn seven and lost four of their 15 league matches this season to collect 19 points, which has left them in 11th position in the table, level on points with 10th-placed Valencia.
Los Franjirrojos have finished 12th and 11th in their last two campaigns back at this level, but they did claim eighth in 2012-13, so it would not be a surprise to see them secure a top-half position.
Francisco's side suffered a 4-0 defeat to Athletic Bilbao in the league last weekend, which made it five games without a victory in Spain's top flight, while they have only managed to win once in La Liga since the middle of September, so there has been a drop-off since the start of the season.
Rayo will enter this match off the back of a positive result, though, recording a 2-0 victory over Yeclano to progress to the third round of the Copa del Rey.
Los Franjirrojos have not actually beaten Celta in Spain's top flight since January 2019, but the points were shared in a goalless draw in the corresponding match during the 2022-23 campaign.
Celta, meanwhile, also triumphed in the Copa del Rey on Thursday, securing their spot in the third round of the competition courtesy of a 2-1 success over Sestao River.
The Sky Blues have drawn their last two in the league against Valencia and Cadiz, meanwhile, with a total of nine points from 15 matches leaving them in 18th position in the table.
Celta have won one, drawn six and lost eight of their games in Spain's top flight this season, but they have only been beaten in one of their last four, and there have been positive signs from Rafael Benitez's side in recent weeks, with this match potentially being used as a springboard.
The Vigo outfit have finished eighth, 11th and 13th in their last three league seasons, but they were 17th in two straight campaigns in 2018-19 and 2019-20, so it is not shocking to see them in the relegation zone.
There is still an awful lot of football to be played this season, and Celta, who have won two of their last three league games against Rayo, have a manager capable of dealing with high-pressure situations.
As for Celta, Joseph Aidoo will miss the match due to a serious knee injury, but the visitors are otherwise in strong shape for Monday's clash.
Head coach Benitez could name the same side that took to the field for the first whistle of the league clash with Cadiz last time out, with Iago Aspas and Jorgen Strand Larsen featuring as the front two.
Rayo Vallecano possible starting lineup:
Dimitrievski; Balliu, Mumin, Lejeune, Chavarria; Valentin, Ciss; De Frutos, Trejo, A Garcia; Camello
Celta Vigo possible starting lineup:
Guaita; Vazquez, Starfelt, Nunez, Sanchez; Mingueza, Tapia, De la Torre, Bamba; Larsen, Aspas
We say: Rayo Vallecano 1-1 Celta Vigo
There is not an awful lot between these two teams when it comes to quality, even if the league table paints a different picture at this stage of the season. Celta are drawing a low of games at the moment, and we are expecting the points to be shared in a tight match on Monday night.
For data analysis of the most likely results, scorelines and more for this match please click here.