Real Sociedad sacked coach Sergio Francisco on Sunday with the team down in 15th in LaLiga, just one point above the relegation zone.
Real Oviedo, 19th, followed suit by ousting Luis Carrion after little more than two months in the job.
Real Sociedad reached the Europa League last 16 last season and finished in mid-table in the Spanish top flight, with Imanol Alguacil departing at the end of the campaign.
The Basque side promoted Francisco from the reserve team Sanse to take his place, but La Real have won only four of 16 league matches during his time at the helm.
On Friday they lost 2-1 at home against Girona, 18th, which sealed his fate.
"Current Sanse coach Jon Ansotegi will be in charge of leading, provisionally, the team into the two matches they have before the Christmas break," said Real Sociedad in a statement.
They visit Eldense on Tuesday in the Copa del Rey before a crunch league clash with Levante, 20th, on Saturday.
Oviedo were thrashed 4-0 by Sevilla on Sunday, spelling the end of Carrion's short and troubled second stint in charge of the club.
Carrion was hired in early October to replace Veljko Paunovic but gained just four points from a possible 24 in his eight league matches at the helm, failing to win a single game.