Mysterio had sustained an ankle injury in the main event of Raw on Monday night, landing awkwardly after flipping over the shoulder of Baron Corbin during one spot. Mysterio worked the remainder of the match in noticeable pain, and his match vs. Andrade on SmackDown Live Tuesday night was cancelled as a result.
As of mid-week, Mysterio's WrestleMania status was up in the air, and the legendary high flyer posted on Instagram that he was just praying to be ready for Sunday.
Meltzer's report adds that Mysterio was reportedly walking around without a limp as of Thursday.
The match on Sunday with Joe marks Mysterio's ninth WrestleMania match, and his first since competing in the first ever Andre the Giant Memorial Battle Royal at WrestleMania 30 in 2014.
Overall, his record at the event, not counting the battle royal loss, is four wins and three losses. Mysterio's most notable win occurred in 2006, when he won the World Heavyweight title at WrestleMania 22, winning a triple threat over Kurt Angle and Randy Orton.