The match between Rayo Vallecano and Osasuna, from the previous performance of Osasuna I don't think that team of Osasuna can be able to defeat Rayo Vallecano, because the last match of Osasuna it played 1:1 against Cadiz and the goal was equalise through penalty base on their pressure to Cadiz so they will not lose this match because their previous match they almost lose the match,it was at die minutes the penalty manifest, so for Rayo Vallecano, they may likely defeat Osasuna because if you go through their history you see that they have a very record they have lose a match and it may be that they will win the match or it ended draw, because both team is of same performance style from my understanding
Osasuna's position in the La Liga standings is currently below Rayo Vallecano and they have a gap of 4 points, but yes, even though based on the odds, the reality is that Osasuna is still quite the favorite to win. But yes, even though Osasuna is quite the favorite in this match, but I personally not sure at all about Osasuna will win this match.
Because after all, in Osasuna's home match record so far, the reality is that Osasuna doesn't have good home results, while regarding Rayo Vallecano's away matches, the reality is that Rayo Vallecano has good away match results at this moment. Therefore, at least I predict that Rayo Vallecano will not lose this match and maybe a draw could occur. But yes, even if for example one of them manages to win, I'm sure their winning goal won't be big and maybe only differ by one goal and therefore, I'm sure this match won't have many goals.