It's the year of the rookie in San Diego. Fifteen players have made their big league debuts in a Padres uniform this season. That number doesn't count Francisco Mejia, who played a few games with Cleveland before he was traded, then homered twice in his first start for San Diego on Thursday.
On Friday, Mejia was slated to bat second against Cincinnati, behind fellow top-25 prospect in baseball, per MLB Pipeline, and recent callup Luis Urias. In total, 20 rookies have suited up for the Padres this season -- and the majority of them have held their own.
After Mejia's heroics on Thursday, here's a look at San Diego's 10 best rookie performances in 2018.
10. Urias vs. Mariners, Aug. 29
3-for-5, 2B, first career hit
Urias' big day could easily be higher on this list, if not for a crew chief review that overturned his first home run in the fourth inning. No matter, Urias still pounded out three hits -- including a double -- and he'd record his first homer two days later, an opposite-field shot to roughly the same part of the ballpark.

9. Robert Stock vs. Mets, July 24
3 IP, 0 R, 5 K's, 1 H
Even the Padres weren't entirely sure what they had in Stock until this late July contest in New York. Stock came out firing, mixing 99-mph heat with a devastating breaking pitch -- and he maintained it for three innings. Stock threw 37 pitches and recorded 10 swings and misses and eight swinging strikes, on his way to racking up five strikeouts.

8. Franmil Reyes vs. Brewers, Aug. 7
3-for-3, HR, 2B, BB, 3 RBIs
Reyes reached base all four times, including a fourth-inning homer that cut the Padres' deficit to one. But his biggest contribution came in the seventh. Facing Brewers ace reliever Josh Hader, Reyes smashed a slider into the left-center-field gap for a go-ahead two-run double. The Padres won the game, 11-5, mostly through Reyes' contributions.

7. Jacob Nix vs. Phillies, Aug. 10
6 IP, 0 R, 4 H, 4 K's, 2 BB
Nix's gem against the Phillies is the only game on this list that counts as a debut (Mejia and Urias put forth their big days in their second game with the Padres). After a shaky first inning, Nix settled in for six brilliant frames on just 88 pitches. He faced 24 batters and didn't allow an extra-base hit.

6. Joey Lucchesi vs. Phillies, Aug. 12
6 IP, 0 R, 2 H, 6 K's, 3 BB
Two days after Nix's gem, Lucchesi was similarly excellent. He, too, worked six scoreless and probably could've gone longer if the Padres weren't already running away with an eventual 9-3 victory. Lucchesi owns a 3.59 ERA through 22 starts, the best for a San Diego rookie with at least 100 innings since Cory Luebke in 2011. This was probably his best performance.

5. Reyes vs. D-backs, Sept. 3
2-for-3, 2 HRs, 4 RBIs
No one disputes Reyes' other-worldly power. He put it on full display Monday in Arizona. Reyes smashed home runs to both fields for his first career multi-homer game, and both dingers were emblematic of his skill set at the plate. The first pitch jammed him, yet he still muscled it out to right-center. The second came on a 3-2 count after he laid off an enticing Zack Godley curveball just outside of the zone.

4. Mejia vs. Reds, Sept. 6
2-for-4, 2 HRs, 4 RBIs
Mejia became the first player in franchise history to homer in the first two plate appearances of his first start with the club. The most impressive part? The bat speed. Mejia caught up with fastballs at 96 mph and 97 mph for his home runs, making him just the third player in the Majors this season to go deep twice in a game on pitches thrown at 96 mph or harder.

3. Nix vs. Mariners, Aug. 28
8 1/3 IP, R, 8 H, 0 K's, 0 BB
Nix had completely avoided any of the three true outcomes until Nelson Cruz's homer in the ninth. Still, Nix did not walk or strike out a Mariners hitter, routinely inducing weak contact en route to 8 1/3 innings of one-run ball. Only Randy Jones has recorded a longer start without a strikeout or a walk in Padres history (Jones pitched a 10-inning complete game against the Giants during his 1976 Cy Young Award-winning season).

2. Eric Lauer vs. Dodgers, July 10
8 2/3 IP, R, 4 H, 8 K's, 2 BB
Lauer's performance against the Dodgers is arguably the best by a Padres pitcher this year. He came one out from becoming the first San Diego rookie to pitch a shutout since Clay Hensley in 2006. Player Page for Max Muncy took him deep, negating that possibility. But Lauer would further endear himself to Padres fans after the game. When asked about his success against the Dodgers, he responded, "It's the Dodgers, man. Nobody likes the Dodgers."

1. Christian Villanueva vs. Rockies, April 3
3-for-3, 3 HRs, HBP, 5 RBIs
From the outset, Villanueva came out slugging this year. In his second start, Villanueva put forth one of the all-time great performances from a Padres rookie, going deep three times in an 8-4 San Diego victory. Villanueva, who is currently sidelined with a broken right middle finger, went on to win the National League Rookie of the Month Award in April.