BOSTON -- For the Red Sox, this was the ultimate payoff on a $1 bet made on a player they'd never seen.
For Daniel Nava -- who was 4-foot-8 and 70 pounds when he entered high school, went to the College World Series with Stanford as a 15-year-old batboy, failed to make his own college team and washed uniforms as the team manager, became a late bloomer but still went undrafted, then was cut by an independent league team, the refuge of last resort -- this was well, we'll let his college coach, Mark O'Brien, tell you.
"That guy," O'Brien said Saturday by telephone from northern California, "I'm sure you could do a movie on him, man."
A grand slam on the first pitch he ever saw in the big leagues, on his first day ever on a big league roster?
"I guess it's pretty ridiculous," Daniel Nava agreed.
On national TV? At Fenway Park in a 10-2 win over the Philadelphia Phillies, the defending National League champions, with his mom and dad among the only folks in the stands who had any idea who he was?
"You're in shock, really," said Nava's mother, Becky. "Just in awe.
"You think maybe you're in a dream."
As Nava was headed to the on-deck circle for that first at-bat, he turned to manager Terry Francona.
"I wonder where my folks are sitting,"' he said to the manager.
"I don't care," Francona said. "Go get a hit."'
Joe Castiglione, the veteran Sox radio broadcaster, had offered similar advice to Nava on the pregame show. The last thing Joe Castig said to the kid?
"Hit that first pitch out."
And when Nava did just that, launching a second-inning fastball from Joe Blanton into the Red Sox bullpen, where Manny Delcarmen would catch it and later present it to the kid as the souvenir of a lifetime, well, this is the part in the movie when men throw their hats into the air, little kids clap and scream, and women blow kisses.
Only one other player in big league history had hit a grand slam on the first pitch he'd seen. That was Kevin Kouzmanoff, with the Indians four years ago (Sept. 2, 2006, versus Texas).
"I'm about to start crying," Francona said afterward. "I guess I'm getting old."
Three thousand miles away, the emotions were no different.
"I had tears in my eyes, man," said Mark O'Brien, coach of the Santa Clara Broncos, who was an assistant at Stanford when he first met Nava at a kids' baseball camp O'Brien ran.
"We took him with us as a batboy to Omaha for the College World Series. I think he was 15, but he looked about 12."
Two years later, O'Brien had the Santa Clara job, and Nava was graduating from St. Francis High in Mountain View, Calif., the same high school O'Brien had attended. Nava batted ninth in the St. Francis order. He didn't hit his first home run until his senior year.
"I hit a ball over like a 3-foot fence," Nava said Saturday. "I was really sprinting around the bases. I'd never hit a home run before. I never knew what it felt like."
In an act of charity more than prescience, O'Brien told Nava he could try out for the Santa Clara team.
"He was about 5-foot-8 and 135 pounds," O'Brien recalled. "He showed up and he could barely hit the ball out of the infield. I told him, 'We'll keep you on as manager,' and he did everything for two years, including washing uniforms."
Don Nava, his father, recalled his son calling him from the road, between the washer and the dryer, with a pocketful of quarters. "He was getting kicked out of the laundromat on a Saturday night in Compton, California," he said.
But O'Brien noticed something else.
"He was shagging flies, hitting in the cages, and kept getting bigger and stronger," he said.
Becky Nava said her son had a growth spurt, tacking on three inches. He also was filling out. But just when he was beginning to look like he could play a little, O'Brien said, his folks ran into a little financial trouble. Staying at Santa Clara was out of the question. So he transferred to a junior college, the College of San Mateo, and hit over .400 in two seasons.
This time, when Nava came back to Santa Clara, it was on scholarship. He led the West Coast Conference in hitting and on-base percentage and didn't make an error. He also didn't get drafted.
He tried out for a team in the independent Golden League, the Chico Outlaws. He was cut from the team. Later that season, they called him back. One of their players had gotten married, and they needed an outfielder.
The Red Sox come late to this story. Jared Porter, the team's assistant director of pro scouting, remembers Theo Epstein and Allard Baird, an assistant to the GM, admonishing the team's scouts in the summer of 2007 to be aggressive in their scouting of independent league teams. Sox scouts get all the stats on the independent league players, and that's when they first noticed Nava.
But it went beyond the numbers. The good scouts cultivate relationships, and Porter had a good one with David Kaval, the president of the Golden League. Porter began asking questions.
"When a kid is playing independent ball, there's usually a reason," Porter said Saturday by phone from Southern California. "But every question we asked, we got back all the right answers. His makeup? Good. Defense. Yes. Arm? Solid. Not great but solid. Switch-hitter, good from both sides? Yes."
"Sometimes," he said, "guys are overlooked. Smaller guys, most don't pan out. But with Daniel, his swing, his makeup, his approach, they were very positive about everything."
From his contacts, Porter learned that a couple of other teams were on to Nava. He made his move. Players can be purchased for $1 after the last game of the Golden League season, which is typically around Sept 15. That's a paper transaction: If a player makes a major league organization, the Golden League receives a total of $1,500. Otherwise, the big league team is out the costs of flying a player to spring training and his expenses, and takes on medical liability while he is in camp.
On Oct. 20, 2007, the same day the Sox were playing the Indians in Game 6 of the ALCS, the Sox agreed to purchase Nava. It wasn't until after he was signed, Porter said, that they sent an area scout to work him out to make sure he was healthy. Nava was 24 -- old for a prospect just starting out, but not too old for someone to take a chance on him.
"And he's raked," Porter said, "ever since we got him."
He hit .341 for Class A Lancaster in 2008. Last season, he hit .339 in Class A Salem, was promoted to Double-A Portland and hit .364 in 32 games there.
He started this season in Triple-A Pawtucket and was hitting .294 with 8 home runs and 38 RBIs when the call-up to Boston came. On Saturday, his old Portland Sea Dogs teammates were watching on TV, cheering for him. It was the same way in Pawtucket.
Becky and Don Nava had been in Indianapolis with Nava, watching him play for the PawSox, and were preparing to return home to California when their son learned he was headed to the big leagues. They quickly changed their plans; they were afraid they were going to miss the game because of a flight delay, but walked into the ballpark just as their son was running out to his position, left field.
Before the day was over, Sox owner John W. Henry would pay them a visit in their seats.
Afterward, Don Nava said he always believed this day would come.
"He was not going to be denied," he said of his son. "I've never doubted him. Never."
Becky Nava said she never thought her son should stop trying.
"If God is going to open that door, he's going to open it," she said. "Doesn't matter what people say."
And what did the kid say of the chances that his odyssey would end -- begin? -- like this?
"I guess it'd be pretty improbable," he said. "But I guess through the whole process I tried not to look too far down the road, because I've always had something in front of me. I had to make a team. I had to get in the lineup, stuff like that. Maybe it was a good thing, to keep focused on smaller goals, to keep me focused."
When Nava hit his grand slam Saturday, he sprinted around the bases. Old habits die hard.
"I told him," Francona said, "'You'll never have another day like this in your life. Enjoy it and play the best you can and help us win.' He did all of those things.
"That swing was gorgeous."
Gordon Edes is ESPNBoston.com's Red Sox reporter. He has covered the Red Sox for 12 years and has reported on baseball for 25 years. Ask a question for his next mailbag here.