"[I thought], 'This could be your last start in high school, or this could be the beginning of something better,'" Thompson told KDAF-TV Dallas/Fort Worth after Monday's game.
Thompson didn't know it at the time, but on early Tuesday afternoon, when he received the call that Detroit had selected him, it would be the latter.
It's also the beginning of a difficult decision the pitcher must make on his future. In November, he committed to play college ball at Texas Christian University. He can elect to receive an education and fine-tune his skills against college opponents, or he can begin his professional baseball career immediately.
In an interview with Scout.com, Thompson said that whatever he chooses, he wants to make sure it's the "smart decision."
"I think everybody wants to play professional baseball, and I do for sure," Thompson said. "It just depends at what point I go [in the Draft] and play ... I just want to make sure that the decision makes sense, and if there is the right opportunity there, I have no problem doing it."
If his Twitter account, @jthomp15, is any indication -- he tweeted, "Absolute honor to be the first pick of the Detroit Tigers!" And then suggested he and third-round pick, and fellow Texas native, Austin Schotts should be roommates -- it sounds like he believes he found the right match.
But that's not unexpected from the Tigers. Tigers vice president David Chadd and scouting director Scott Pleis are very careful when it comes to taking high school players. They closely examine "signability," which is a reason that 12 of their 14 picks on Day 2 and 24 of their 29 picks in 2011 were college athletes.
"I think it just worked out that the high school players that were available at the time that we liked were there and were signable guys," Pleis said.
Make no mistake about it: Pleis, Chadd and the rest of the Tigers organization didn't only like Thompson because they believed they could sign him.
Pleis said Thompson has "the whole package," noting his great arm and competitive nature. Chadd was a little more specific, stating that he liked his mix of a 92-94 mph fastball, slider and changeup that helped the 6-foot-4, 235-pounder compile 130-plus strikeouts and an 11-1 record his senior year.
"[He's a] typical power Texan right-handed pitcher," Chadd said. "Very confident in his ability. There's a lot of other kids that played against Jake that went off rounds before and right after that he faced this year and had success [against]."