NATICK — The Walpole baseball team only had its offense going for one inning in Saturday’s Division state semifinal.

But, boy, what an inning it was.

On the strength of a five-run bottom of the fifth, Walpole had just enough to slip past Westwood, 5-4, and advance to the Final Four, where it will face Milford.

No. 1 Walpole’s season continues at 19-4, while No. 9 Westwood’s ends at 16-7.

Westwood led 3-0 before that pivotal fifth, a spot Walpole does not usually find itself and live to tell about it.

“Senior leadership, first and foremost,” Walpole coach Chris Costello said. “We haven’t been in that position. I don’t know if we have been down three and come back. Typically, we like to get out early and then stack and ride or pitching and defense. In that regard, today was all about our seniors and their leadership riding the storm, so to speak.”

For most of the game, Westwood starter Luke Chandler was making quick work of the Walpole batters, and Westwood grabbed that 3-0 lead.

But Walpole found success in the fifth, as Paul Whelan, son of Westwood coach Brian Whelan, led off with a base hit to center. Shane Harrington was hit by a pitch. After a strikeout, Michael Corrigan walked to load the bases. Kyle Jordan followed with Walpole’s biggest blow, a ground-rule double to center to plate Whelan and Harrington.

“I knew in that at-bat, that was definitely the key at-bat of the game,” Jordan said. “I knew I had to do something there. I wanted to stay calm, stay in place with my approach. After that, I went with what I’ve always done throughout the season and hit a nice, solid hit to center field.”

Westwood brought in Elliot Harris in relief, and Ryan Walsh took another hit by pitch to load the bases again. An error brought in Corrigan to tie it, then another scored two more runs to account for the 5-3 Walpole lead.

The Wolverines got one back in the sixth, as Julian Colon (3-for-3, two doubles, HR, two RB) doubled to lead off, and came in on a sacrifice.

Westwood had one more chance to tie it in the seventh, as the Wolverines had two runners on, but Harrington at shortstop flipped to Jordan on a grounder up the middle to end it.

“Credit to (Brian Whelan) and Westwood,” Costello said. “I would say they’re the closest thing to what we do as a program. (Whelan), we’re very familiar with each other. Obviously, his son plays for us. We coached together, the 2019 Little League state title team, (Whelan) and I coached together on that team. He’s a good man. He’s a hell of a coach. All those guys, it’s what we expected.”

Westwood scored in the first when Colon’s double plated Alex Dayton off Walpole starter Alex Hee. Hee (six strikeouts) then struck out the side in the second.

Harris scored in the third when he reached on an infield single and came around on a sac fly to center by Jon Bertone. Colon made it 3-0 in the fourth when he blasted a home run to dead center.

But Walpole rallied in the fifth, and that was enough.

Westwood’s Elliot Harris makes a diving stop on a ground ball hit by Walpole’s Kyle Jordan for an out during the fourth inning. Walpole collected a 5-4 victory. (Photo by Paul Connors/Media News Group/Boston Herald)