The surgeon who operated on Tejano singer Emilio Navaira is now "optimistic that he will not die," just a day after warning fans to expect the worst.

The Grammy Award-winning star is in a critical condition following a tourbus accident in Houston, Texas, which took place on Sunday morning.

The 45-year-old and his band Rio, who performed in Houston on Saturday night, were traveling on interstate 610 when their bus collided with two other cars, almost tipping over in the process. Eight people, including driver Navaira, were taken to the Memorial Hermann Hospital following the incident.

On Tuesday, Dr. Alex Valadka, who performed an operation to remove a blood clot from the singer’s brain on Sunday, admitted Navaira may not survive.

But on Wednesday, Dr. Valadka’s diagnosis was that Navaira’s condition had improved slightly. Dr. Valadka said, "I feel optimistic that he will not die. He’s done about as well as can be expected." But the surgeon cautioned, "He can still take a turn for the worse."