For the right-handed-hitting slugger, this game has been a long wait for two entirely different reasons.
The first is the obvious. Napoli didn't start the three games in St. Louis because Boston lost the designated hitter, while playing in a National League park, and the hottest hitter on Planet World Series (David Ortiz ) needed to play first.
The second goes back a couple of years. It was Game 6 of the 2011 World Series in St. Louis. Napoli was going to win his first World Series ring.
A catcher in those days, Napoli squatted behind the plate and put his glove out, hoping to catch the final pitch of a championship. His team was a precious one strike away as Napoli gave closer Neftali Feliz the sign for a fastball.
But instead of mobbing his teammates, Napoli was left to take his mask off and witness the horror of David Freese belting a two-run triple over the head of right fielder Nelson Cruz to tie the game.
"Feliz threw 98 [mph]. It was a fastball away," said Napoli. "He got his barrel to the ball and got a hit."
It was all going to be OK when Josh Hamilton belted a two-run homer to put the Rangers back on top, 9-7, in the 10th.
Napoli went back out for defense for the bottom of the inning, again with hopes high. And again, he was one strike away. Another hitter broke Napoli's heart -- that time, it was Lance Berkman who tied it with a single.
Of course, the Rangers would lose an all-time classic World Series game, 10-9, when Freese went deep in the 11th, again with two strikes. Texas lost Game 7, 6-2.
Napoli couldn't be any more excited to play another Game 6 of the World Series, but he knows better than anyone about the importance of staying on task and not getting ahead of the moment.
"I've been there before," Napoli said. "I was one game away -- Game 6 -- and ended up losing it. I don't get too far ahead of myself. I want to go out there and put a good game together and try to win."
The big difference, as far as Napoli is concerned, is that the Red Sox are at Fenway Park for the final two games of this World Series. His Rangers were playing on the road in front of a rabid St. Louis crowd.
"We feel comfortable playing there, it's our home field," said Napoli. "We'll have our crowd behind us. It should be fun. We're not going to change anything. We're going to play our game and try to win a ballgame."
Napoli loved watching Boston take two out of three in St. Louis, but he's extremely eager to start aiding the cause again and trying to win the close-out game that he couldn't two years ago.
"Yeah, I'm excited," Napoli said. "It was kind of rough being in the dugout and I wanted to be in there, but it was [Ortiz] at first base. I can't really complain about that. He's one of the best hitters in the game. I was ready for the late innings."
Napoli now will be ready for all innings, and Ortiz will have his big protector behind him again in the batting order.
"With Mike Napoli at first, it gives us some additional range," said manager John Farrell. "But getting one of our middle of the order bats back to us, we're hopeful that it really has a chance to extend the lineup even that much more."
In Game 1 of the World Series, it was Napoli who provided the bases-clearing double in the bottom of the first. He belted two pivotal home runs in the American League Championship Series.
If Napoli can come through again, it could go a long way toward helping the Red Sox win the whole thing. The offense, beyond Ortiz, has been spotty, even with Boston holding a 3-2 lead.
Again, though, Napoli will try not to think so much about the lead and instead focus on what he can do to help the Red Sox put away the Cardinals.
"I'm always that type, until you've done it, it's not done," Napoli said. "That's how I've always been with everything."
What does he remember from two years ago, before the bad stuff happened?
"I remember the feeling of being excited. I'm going to be excited Wednesday. I think I feel the same, but I really don't remember exactly," Napoli said. "You're going to have that butterfly feeling. It happens throughout all the playoffs. I remember being close and feeling good, but it still wasn't done."
And therefore, Napoli knows the one thing that still is left to be done for this Red Sox, and that's to get that fourth World Series win in any way possible.