If you happen to see Wallace Johnson at the Montreal Jazz Festival this summer, stop and buy the man a drink.

After all, the former pinch-hitter extraordinaire, who frequently returns to the city for this landmark event, was the author of arguably the most important hit in Montreal Expos history.

His two-run triple off of New York Mets closer Neil Allen in the seventh inning of the second last game of the 1981 campaign helped catapult the Expos into the post-season for the first – and only – time in franchise history.

“Being a call-up from Triple-A, I wasn’t sniffing very much playing time, so when Mr. (Jim) Fanning called me off the bench (to pinch-hit for Bill Lee) – I remember I was sitting between Warren Cromartie and Bill Gullickson – I was a little bit shocked,” recalled Johnson in a phone interview this past January. “But I grabbed my bat and went to work. Obviously my manager had confidence in me. He knew what I did in the minor leagues and he wasn’t afraid to use me in that spot.

“I remember Neil Allen, being that premier closer, was trying to intimidate me as a young player. I’ll never forget that. That was fun. I was able to make contact and it found a spot. I didn’t really realize what was happening. It was a triple, but I didn’t realize it was going to be that big of a hit.”

That triple – Johnson’s second and final hit of the regular season – would put the Expos ahead 4-3 in the game in which they would clinch the second-half division title.

That hit was the highlight of Johnson’s nine-season big league career that, with the exception of seven games with the Giants in 1983, was played entirely with the Expos.

Born in Gary, Ind., on Christmas Day in 1956, Johnson was selected in the sixth round of the 1979 amateur draft by the Expos. Predominately a second baseman in the minors, Johnson would be used almost exclusively as a pinch-hitter in the majors.

That September call-up in 1981 represented his first taste of big league action.

“1981 was a magical year. We won the championship in Triple-A, and Felipe Alou was the manager there in Denver, and then to get called up in the middle of the pennant race,” reflected Johnson.

Though he would never return to the post-season with the Expos, Johnson evolved into one of best bench weapons in major league history. He led the National League in pinch hits for four consecutive seasons from 1987 to 1990.

After he hung up his spikes as a player, he coached in the Atlanta Braves organization from 1995 to 1997, before serving as the Chicago White Sox third base coach from 1998 to 2002 under former Expos teammate Jerry Manuel, who was managing the club at the time.

Johnson now runs his own non-profit baseball academy in his hometown of Gary, Ind., and in West Palm Peach, Fla.

The charismatic former Expo remains in touch with a number of his Expos teammates, including Cromartie and Manuel. He also made the trek to Cooperstown for Andre Dawson’s National Baseball Hall of Fame induction ceremony in 2010 and again last year to watch broadcaster Dave Van Horne receive the J.G. Taylor Spink Award.

He hopes to return to Cooperstown for the induction of Tim Raines, another of his longtime teammates, in the future.

“That’s one guy that I’m amazed that folks didn’t realize how great he was. He could do anything he wanted on the ball field. And I hate to make comparisons because I get in trouble, but if Rickey Henderson is in the Hall of Fame, Tim Raines should be in the Hall of Fame,” said Johnson. “I think ‘Rock’ brought much more than just base-stealing. He was a switch-hitter that won a batting title. He could do all kinds of things. I think without a doubt he should be in the Hall of Fame. I’m his No. 1 booster here in Gary, Indiana. We’ve got Andre in there, we’ve got Gary (Carter) in there, Dave Van Horne and now we need to get ‘Rock’ in there.”

In that late January interview, Johnson also shared memories of Gary Carter, just prior to The Kid’s death.

“I think what I remember most was his unabashed enthusiasm,” said Johnson. “He was always full of spirit and full of fight and he led us to war . . . He worked hard. You knew it was going to be a fight to play the Expos with him behind the plate. He was just a gamer. If you look up the definition of a gamer, it was Gary Carter . . . Gary would give you the shirt off his back. He was a great Christian guy that I was just blessed to know.”

Johnson still regularly returns to Montreal.

“I always try to go back to the jazz festival,” he said. “That became one of my favorite things to do in the summer time. I haven’t been there in a couple of years. There’s also a gospel concert every December that I try to attend. I definitely try to get back up there, but now that the U.S. dollar is so weak, I have to watch myself. I have to really budget to get up there. But I really enjoyed playing and living there and I brag about the city continuously.”