The 27-year-old rookie had just thrown baseball's first no-hitter this season, in his 13th major league start, and here he was in the interview room, flanked by San Francisco manager Bruce Bochy and catcher Buster Posey, trying to detail a most unexpected moment.
''Definitely something I'll remember forever,'' Heston said
In a championship rotation filled with All-Stars, his name is the one that sticks out as lacking pedigree.
He is far from the prototypical major league pitcher.
Drafted on the 47th round, he stayed in school.
Drafted on the 29th round, he stayed in school.
Taken on the 12th round, he finally signed with San Francisco in 2009.
And in an era of radar gun worship, Heston didn't throw a pitch faster than 91 mph.
''It's not always how hard you throw,'' Bochy said. ''It's your command. It's your ability to mix up your pitches, keep them off balance, hit your spots, pitch to your defense. Sure, it's nice to have that 95-99 (mph), but if you're off a little bit, hitters are going to catch up with that, trust me.''
Heston (6-4) allowed three baserunners - hitting Tejada, Lucas Duda and Anthony Recker with pitches. According to STATS, it was the third no-hitter since 1914 in which all the runners who reached did so on hit batters - and the first with more than one.
Heston called it the greatest moment of his life.
''This has got to be No. 1, probably right next to my first big league appearance,'' he said.
After freezing Tejada with a 91 mph sinker for the final out, Heston didn't jump, didn't raise his arms in triumph.
He hopped off the mound with two steps toward the Giants dugout, slapped his glove with his bare hand, then turned, walked toward home plate and hugged Posey.
''I wasn't too sure where to go after that last out,'' Heston said in an aw-shucks manner, looking boyish despite a day or two of stubble.
He took the ball from the final out with him, but didn't have any designated place to display it. He doesn't have a trophy case.
''I don't have enough stuff for one,'' he said.
While the Giants win the World Series in even-numbered years lately - 2010, `12 and `14 - they have turned no-hitters into an annual fixture, with Heston following Matt Cain's perfect game against Houston in 2012 and hitless gems by Tim Lincecum in 2013 and `14. The only other team to accomplish the feat in four straight years was the Los Angeles Dodgers - all by Sandy Koufax - from 1962-65.
As a crowd of 23,155 looked on at Citi Field, the closest the Mets got to a hit was in the eighth, when Brandon Crawford made a backhand stop deep at shortstop and threw to first to retire Eric Campbell for the final out of the inning.
''It took kind of an in-between hop. It wasn't an easy one, for sure,'' Crawford said. ''That was about the toughest play of the game. Usually, there's a really good play that saves a hit, or maybe some hard line drives right at somebody. But there really weren't a lot of balls squared up.''
The Mets, who had not been no-hit at home since 1969, hadn't gone hitless in any game since 1993 - the fourth-longest current streak behind the Chicago Cubs (1965), Oakland (1991) and Boston (1993), STATS said.
''Obviously, those guys would have helped tonight, there's no question of that. But you don't want to take anything away,'' Cuddyer said. ''He had a really good sinker and he kept everybody off balance with a couple of different kinds of breaking balls.''
Heston threw 72 of 110 pitches for strikes in the 35th complete-game no-hitter by a rookie in major league history, according to STATS, the first since Boston's Clay Buchholz in 2007.
Heston made his big league debut last Sept. 13 against the Los Angeles Dodgers but was sent to the minors on March 20.
''The numbers really got him more than anything,'' Bochy said.
But when Cain started the season on the disabled list, Heston was brought up April 7. Before Tuesday, his only complete game was a two-hitter against Houston on May 12. Heston was knocked out in fourth inning against Pittsburgh in his previous start.
''Honestly, I think it's just a matter of him just kind of trying to find his way right now,'' Posey said after catching his third no-hitter. ''He's still early in his career in establishing what type of pitcher he's going to be. And it's something that we all go through when we first get here.''
Bochy, who won his 700th game as Giants manager, had an easy night in the dugout through eight innings. Then Heston plunked Recker to start the ninth.
''I said, `Well, what's going to happen if he hits the first three? Do I get him with a no-hitter?''' Bochy remembered.
No way. Old-school Bochy was going to let him keep on going.
''I think you know about my pitch count,'' the manager said. ''I watched Timmy throw close to 150, so he probably could have thrown 50 the last inning.''
When Heston returned to the Giants' clubhouse, he was met by one last ovation, this time from all his teammates.
''It was awesome, to walk in and having the whole team sitting there, congratulating me,'' he said. ''Definitely a special moment. I'll remember that forever.''