Neagle set up their first goal, was the man taken down in the penalty area that led to their second, then scored the third one himself the game-winner in the 81st minute to cap a come-from-behind 3-2 victory over the Vancouver Whitecaps in front of 53,679 fans at CenturyLink Field.
Neagle, who has taken a more prominent scoring role with the Sounders while forward Eddie Johnson is with the U.S. national team, ran onto a short pass from Obafemi Martins and drilled the shot into the back right corner from just inside goalkeeper Brad Knighton's 6-yard box.
"It was a good buildup play down the right side," Neagle said. "I saw (Martins) one-on-one, so once he made his move toward the line to beat his guy, I knew I had to get in front of my defender, and it would be an easy pass right to the near post."
Neagle has four goals and three assists for the year.
"That third goal was as well-taken a goal as you want to see," Sounders coach Sigi Schmid said. "I was proud of our character in being able to come back. I thought we started off the game well and got the early goal. Then we sort of fell asleep right after we scored, which is a time you can't fall asleep, and we took a goal.
"We didn't go a good job on set pieces, and set pieces got them back into the game those were their most dangerous moments," Schmid said. "The second half, we just talked about making sure we continued to spread out the field and find gaps."
The Sounders (6-4-3, 21 points) had an early 1-0 lead on a goal by Andy Rose before Camilo Sanvezzo scored a pair of first-half goals for the Whitecaps (4-5-4, 16 points).
That 2-1 lead stood until the 70th minute when Servando Carrasco converted a penalty kick, lifting the Sounders into a 2-2 tie. Neagle was taken down in the right side of the penalty area by Vancouver's Greg Klazura. Referee Hilario Grajeda immediately pointed to the spot, and Carrasco launched the kick into the upper left corner over Knighton's outstretched hands.
Carrasco's PK was his first MLS goal.
"I just knew I had to score. It was an important time in the game, and there was only one thought on my mind: Put it in the back of the net," Carrasco said.
Midfielder Rose put the Sounders on the board at the outset of the ninth minute. Neagle sent a through ball toward the right side. Rose broke behind the Whitecaps' defense, took it alone into the penalty area, and sent a 15-yard shot into the back left corner for his first of the season.
Sanvezzo's goals in the 10th minute and the 25th were both assisted by Russell Teibert. Sanvezzo has five goals for the year.
Barely a minute after the Whitecaps fell behind, defender Lee Young-Pyo sent a long ball deep into the Seattle end. Teibert caught up with it just before it would have rolled over the goal line on the attacking right side. He floated a target ball across the area, and Sanvezzo, from the top left of the 6-yard box, headed it into the back right corner.
Those two connected again midway through the 26th minute. Teibert took a free kick 35 yards up toward the right side. He sent it toward the top of the 6, and Sanvezzo's diving header beat goalkeeper Michael Gspurning to the back right corner.
"I just tried to stay in good position and make a good finish," Sanvezzo said of his two headers. "It was very disappointing not to get the point here. I think everybody had a good game, but we just need to pick it up a little bit."