SEATTLE — Brad Wieck entered rarified air without throwing a pitch on Tuesday. In receiving his first call-up, the 6-foot-9 lefty arrived at Safeco Field as the Padres’ tallest player and maybe the tallest active player in the major leagues. He remained in the bullpen throughout a 2-1 victory over the Seattle Mariners, a contest devoid of low-leverage opportunities for a newcomer.



Yet Wieck, while impossibly long-limbed, is far from unique in the broader context of this season. When the 26-year-old next towers over a mound, he will become the 16th, and likely last, player to make a big-league debut with the 2018 Padres.



The discovery phase is far from over, of course. The majority of San Diego’s best prospects have yet to surface, which means this year has been of heightened importance for young major leaguers seeking to establish themselves. Below are assessments of the players who already have debuted for San Diego, beginning with a second baseman...