Manu Ginóbili and the Spurs survived to play another day.
The Argentine veteran paced the team with 33 points, but in the end, it was an undrafted rookie who kept San Antonio from an embarrassing playoff exit against the Memphis Grizzlies.
Gary Neal dropped in a three pointer with 1.7 seconds left as time expired.
"It felt good. I knew I had good legs going into it," Neal said. "It felt good. I followed through and it went in."
The Spurs won 110-103 Wednesday to force a Game 6 in the first round of the western conference NBA playoff series.
The eighth-seeded Grizzlies still lead the best-of-seven series 3-2. They will host the Spurs on Friday night, but left town knowing they missed a knockout punch.
"They're down by three, you've got to run them off the 3. You can't let nobody shoot an open 3," Grizzlies forward Zach Randolph said. "You've got to contest the 3, you've got to deny the ball."
The straightaway 3-pointer was the second of two remarkable San Antonio baskets in the final 2.2 seconds of regulation.
Ginóbili, who missed Game 1 because of an elbow injury, hit the other with a long corner jumper while falling out of bounds in front of the Spurs bench, in what was originally ruled a 3.
A video replay confirmed Ginobili's left toe was on the line. That left the Spurs still trailing 95-94, and after two free throws by Randolph, San Antonio needed another miracle.
Ginobili? Parker? Duncan, in perhaps a repeat of his memorable tying 3-pointer with 3 seconds left against Phoenix in the 2008 playoffs, before the Spurs went on to a double-overtime win?
They drew it up for Neal, a 26-year-old rookie and former European journeyman who the Spurs signed this season after giving him an audition on their summer league team.
"You really don't think about the magnitude of making or missing it, you just think about trying to get the best shot that you can get," said Neal, who finished with seven points. "It went in today, but I think it's the best shot I could have got in that situation."
Randolph led Memphis with 26 points and 11 rebounds. He scored 18 points in the fourth quarter and overtime, but the Spurs assured a Game 6 in the overtime behind Parker, who scored 6 of his 24 in the extra period.
Only eight teams in NBA history have ever come back from a 3-1 deficit. The Spurs, who were the NBA's winningest team for most of the season, are desperate to join that list in what may be their last good shot to win a fifth championship in the Duncan era.
Memphis remains on the verge of becoming just the fourth No. 8 seed in NBA history to win a playoff series. Not since Golden State upset Dallas in 2006 has a No. 8 seed toppled a No. 1 in the first round.
Marc Gasol dominated the glass for Memphis. In addition to his 17 rebounds, the Spaniard center scored 11 points.
Based on reporting by The Associated Press.