Before falling asleep, he couldn't avoid thinking about the many heartaches he's faced over the past 2 1/2 years, during which he's missed two consecutive seasons while recovering from separate left elbow surgeries and heard the cries of the critics who believe his career is complete.
While Hampton's mission to prove these critics wrong is far from complete, it's definitely progressing smoother than ever imagined. A month ago, the Braves might have been hopeful he'd start the season in their starting rotation. Now they'd be surprised if he didn't.
"I expect that he will be [in the starting rotation]," said Braves manager Bobby Cox after watching Hampton limit the Astros to just one hit in two scoreless innings of Sunday afternoon's 6-4 win at Disney's Champion Stadium.
From a factual standpoint, it was just two innings in a Grapefruit League game against a Houston lineup that didn't include Lance Berkman or Carlos Lee. But the emotional angle to the afternoon stemmed from the fact that Hampton was pitching against a team wearing Major League uniforms for the first time since Aug. 19, 2005.
"I'm not going to downplay the importance that I felt," Hampton said. "It was definitely a big step to get out there, face competition again and come out of it feeling pretty good about it."
After he returned to the clubhouse and showered, Hampton found his phone filled with congratulatory text messages. Jokingly, he said it was as if he'd just pitched Game 7 of the World Series.
"There were a lot of people who had their eye on this game, because they know how important it is," said Hampton, who surrendered his only hit when Jose Cruz Jr. buzzed the mound with a one-out liner to center in the second inning.
Cox was among those who understood the emotional significance of the afternoon. Over the course of the next seven months, he would like to be able to rely on Hampton's arm. But for this one day, he was just happy to see it in action again.
"I was really, really proud of Mike today and happy with the way it turned out," Cox said. "He looked really good."
For the first time since throwing a two-hit shutout against the Astros at Turner Field on May 8, 2005, Hampton said he was able to take the mound without any concerns about his elbow.
One week after that 2005 start, he began feeling the discomfort that would force him to undergo Tommy John elbow ligament replacement surgery four months later.
Hampton's scheduled return for the 2007 season was nixed when it was learned a tendon hadn't reattached after that first surgery. Simply making this one appearance puts the 35-year-old hurler ahead of last year's Spring Training, when he never pitched more than a simulated game.
But while not feeling any elbow discomfort over the past few months, Hampton had already determined things are much different this year. Now he's just hoping to regain some of the leg strength he lost during his long absence and while rehabbing the right hamstring strain that he suffered in November, while pitching in the Mexican Winter League.
"I feel like my arm is sound," Hampton said. "It's just going to be a matter of getting my body in pitching shape."
Hampton admits he still can't pitch without being conscious of the hamstring. He's doing some light running and has at least taken some swings during batting practice. But until he's truly tested to react to game action, he won't have full confidence that it's healthy.
Because he didn't want Hampton to bat on Sunday, Cox agreed to play with designated hitter rules.
"Today was just one step out of about a six-step process that I need to get through to get there," Hampton said. "I'm pretty happy with where I'm at."
Cox was most impressed with the fact that Hampton's command, which showed as he threw 15 of his 22 pitches for strikes and was able to get his patented sinker to induce three ground-ball outs. One of his fastballs was clocked at 93 mph, which is as hard as he threw before the elbow problems began.
"The ball is moving and he had life on it," Cox said. "He hit 93 [mph], which he never does. So he's stronger than ever."
Having found previous pitfalls in this long journey, Hampton isn't ready to celebrate yet. But he admits this start was just as important and maybe even more important than the Spring Training appearances he made in 1993 and '94, when he was attempting to begin life in the Majors.
Now his stress stems from the reality that he's fighting to preserve his Major League life.
"There were a lot of thoughts and emotions that went through my head today," Hampton said.
Mark Bowman is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.