Both Cesar and Peguy Luyindula annulled their contracts with Levante on Wednesday, with the French striker subsequently securing a move to Paris Saint Germain.
The duo joined the Valencia-based outfit last summer but have been little more than bit-part players.
Cesar, who arrived from Deportivo La Coruna, has made only one league start all season and was sent off in that match - a 3-0 defeat at home to Atletico Madrid back in November.
It was thought Bolton would push through a deal to capture him before the transfer deadline but ultimately no such move materialised.
It now looks likely the stopper will have to sit tight until the summer unless he secures a switch away from Europe.
Also on his way out of the club is Luyindula (pictured) who arrived on loan from Marseille at the start of the campaign.
The 27-year-old endured a miserable time in Spain, he managed only two starts and did not find the net during his stay.
The former Lyon man will now be hoping to relaunch his career in France having signed a three-and-a-half year deal with PSG.