BELCHERTOWN – Thatcher Rudnik visualized the last out all day. He knew he was going to close the game out and he knew how he wanted to end it.

Turns out real life played out just like his daydreams.

Rudnik struck out two in the seventh inning, including a fastball for a swinging strike on the last pitch of the game to seal a 6-5 win for Belchertown Post 239 on Wednesday night. It extended their undefeated season to 18-0-1, and the team repeated as District 3 American Legion baseball champions.

“I was thinking about it, that last out, that last strikeout,” Rudnik said. “Going in there and blew it right by him.”

Despite the best efforts of Aldenville Post 337 and Easthampton left fielder Topher Reardon (four RBIs), Belchertown Post 239 held on for the win. Post 337 tied Post 239 4-4 in the fifth and again 5-5 in the sixth, but Williston Northampton’s Jacob Smith hit a game-winning sacrifice fly in the bottom of the sixth to put Belchertown ahead 6-5.

“When it came down to it,” Smith said, “the playoff games, the ‘oh, are we going to keep our undefeated season?’ It came down to we’re in the dugout, having a blast, going up there, no pressure whatsoever. There was a target on our back all year and we really didn’t see it.”

Belchertown took a 1-0 lead in the first inning on an RBI single from Belchertown’s Brady Perkins (Belchertown, Framingham State) and then rode strong pitching from Hopkins Academy’s Chace Earle into the fifth. Earle struck out two batters in each of the first four innings before running into trouble in the fifth, when Reardon jacked a three-run homer over the center field fence to knock him out of the game.

Belchertown’s Jake Waller took over for Earle but promptly loaded the bases and walked in a run to tie the game  at 4-4. The two teams traded runs in each of the next three half innings on a Cody West (Hopkins) RBI double, a Reardon sacrifice fly and the Smith sacrifice fly.

“All year long, when we needed big moments, at-bats, pitches, whatever, we’ve been able to deliver,” Post 239 coach Todd McDonald said. “And this was just one more example of that.”

McDonald said that he wasn’t considering the prospect of a repeat title after last year’s triumph, but once he saw the names on the roster and how Belchertown played in the early part of this season, he began to believe in it.

“The goal of repeating is fun to think about,” McDonald said. “But it’s a nearly impossible, overwhelming task if you think about it.”

Six players from last year’s District 3 tournament-winning team came back this year – West, Smith, Perkins, Cooper Beckwith (Hopkins) and Belchertown’s Derek Gould and Ian McDonald. On top of the six returners, Post 239 moved a few junior legion players up (like Rudnik) and recruited a few old teammates, including Pat Fitzgibbons (Hopkins Academy, Assumption), who nailed a runner at the plate from deep center field to end the fourth inning.

Last season, Post 239 went 1-2 in the double-elimination state tournament. This time around, they enter the tournament undefeated, and they’ve set a goal of trying to better that mark this year. Their first game is on Saturday at 1 p.m. at Fitton Field on the campus of Holy Cross in Worcester.

“A lot of teams in the east and in central Mass. don’t take western Mass. baseball seriously at all,” West said. “Teams look over us. We’re going to go out there and play our game with the group of guys we got and kick some a**.”