With two outs and men on second and third in the 10th, Alec Bohm hit a little dribbler off Evan Phillips (1-2) to Muncy at second for what appeared to be the final out of the inning. But Muncy didn't field it cleanly, dropping it and allowing the ball to roll a few feet behind him.
"I just didn't give myself enough space knowing the ball was going to bounce a little higher on a dry field," Muncy said. "The ball hopped up on me and I just didn't make the play. I came charging in and stopped and didn't give myself enough space knowing it was going to bounce higher."
That sequence allowed Garrett Stubbs to score the tying run and Roman Quinn to bring in the winning run with a head first slide just ahead of the throw home.
"It was one of those in-the-moment decisions," said Quinn, who had singled to keep the inning alive and advanced to second as Stubbs beat a Mookie Betts throw to third. "I peaked back and I saw that he had missed the ball. I'm looking and seeing it out of the corner of my eye, but then (third base coach Dusty Wathan) sent me home."
"I knew there was going to be a play at the plate," Muncy said. "Roman Quinn's really fast. There was a couple of foul balls that he was already at third base by the time the ball was even getting into foul territory, so it's just one of those things where you know, if it gets away from you, he's not going to stop running. It took me too long to find the ball. I felt like I put a good throw on it, but just took too long."
Stubbs had hit his first major league homer to get Philadelphia on the board in the sixth. The Phillies had tied the game with two outs in the ninth on Jean Segura's single to left that scored Nick Castellanos, whose two-out double started the rally.
Corey Knebel (1-3) pitched an inning to get the win.
Trae Turner had three hits for the Dodgers -- including a single that had given the Dodgers a 3-2 lead by scoring Betts. Turner now has a 14-game hitting streak -- tying Paul Goldschmidt for the longest in the National League this season.
Mookie Betts and Edwin Rios hit solo home runs while Tony Gonsolin struck out seven and allowed only one walk and three hits in the no-decision.
"We just didn't make a pitch here or make a play here," Dodgers manager Dave Roberts said. "Give us credit because we kept playing. Unfortunately, we came up short today."
The Phillies received a strong outing from starting pitcher Zach Eflin, who struck out a career-high 12 while allowing four hits and walking two during his seven innings of work with a large number of curveballs in his arsenal.
Eflin's only real hiccups came in back-to-back innings on a pair of hanging sinkers against the top of the Dodgers order. With two outs in the third, Betts generated his 10th homer of the year and his second in as many days with a blast into deep left-center. Then in the fourth, Rios sliced an opposite-field homer that just snuck over the wall in left field.
"It sets the tone for our road trip," Eflin said. "It is important for us to take this on the road. We had some great defensive plays late in the game and getting the run in- that was the definition of a team win. We're all pretty pumped here."
Phillies OF Mickey Moniak was scheduled to have a second rehab assignment start for Class A Clearwater on Sunday before getting transferred to Double A Reading to continue his ramp up following a broken right hand suffered at the end of spring training. When he returns, Moniak -- the top pick in the 2016 Major League Baseball Draft- will likely end up as Philadelphia's primary centerfield option. ... SS Didi Gregorius was expected to fly with the club on its charter to continue the rehabilitation for his left knee sprain that has placed him on the injured list since May 5.
Dodgers: Travel to Washington to begin a three game set against the Nationals on Monday. Tyler Anderson (4-0, 4.04 ERA) will start the opener against Nationals RHP Joan Adon (1-7, 6.38).
Phillies: Start a seven-game divisional road trip in Atlanta on Monday. Zack Wheeler (2-3, 3.49 ERA) will face LHP Tucker Davidson (1-0, 5.87) in the series opener.
Phillies walk it off on Muncy's blunder
Phillies walk it off as Max Muncy bobbles the ground ball from Alec Bohm, resulting in two runs.