That self-possession never wavered. In 1993, the fine-art photographer Andrea Modica visited the Yankees’ spring-training camp in Tampa for her project on young ballplayers. She was working with an 8-by-10 camera, which required a collaboration between artist and subject: each sitting lasted for about 15 minutes, a pretty long time to hold any expression. Modica was captivated by the anxieties in her young and athletic subjects, particularly the minor leaguers hoping to make the team for the first time. “But Derek didn’t have that tension,” she says. “He was elegant.” Modica’s photograph of the 18-year-old — note the early-’90s fade! — did not make it into her book and exhibition. It has never been published until now.

Over the 19 seasons he has played in the major leagues since this picture was taken, Jeter, who will retire this fall, has led the Yankees to 16 postseason appearances and five World Series titles. He has hit better than .400 in 10 different playoff series and is the all-time playoff leader in singles and doubles and is tied for the lead in triples (he is third in home runs and fourth in R.B.I.). Even if he was never the best player in the league during any given year — he never won an M.V.P. award, like the shortstops Alex Rodriguez, Miguel Tejada and Cal Ripken Jr. — he was almost certainly the best shortstop of his generation. His prime lasted until his late 30s, and he played his entire career at the game’s most difficult position, after catcher. His ultimate plus tool might have been the surreal equilibrium on display from the start.

Scouting is an inexact science, especially when its subjects are teenagers. The Yankees’ top pick the year before they drafted Jeter was a pitcher named Brien Taylor, a can’t-miss phenom — who got in a bar fight and never pitched in the majors. In the end, though, Groch got this one right. The five players drafted before Jeter (including Jeffrey Hammonds) made a combined total of two All-Star appearances. Jim Pittsley played 81 games in the majors. “The report I wrote,” Groch said, “it’s exactly what he became.”