SAN DIEGO -- The Padres' 2019 season ended with disappointment, but their first half offered plenty of reason for optimism. Rookies Fernando Tatis Jr. and Chris Paddack burst onto the scene, while Manny Machado arrived in San Diego and quickly made an impact.

Thus, it should come as no surprise that each of the Padres' top five games from 2019 took place before the end of June. Here's a look at those five games and what each of them means for 2020 and beyond.

1. Renfroe's grand walk-off
May 5 vs. Dodgers

The first series between the Dodgers and Padres in 2019 proved to be a thriller. Machado rocked three homers in his first six at-bats, but Los Angeles rallied in the ninth to win each of the first two games. Hunter Renfroe flipped that script in the finale. He became just the 16th player in Major League history to hit a pinch-hit walk-off grand slam with his team trailing. Renfroe's slam capped an 8-5 victory. It was the most electrifying game at Petco Park in 2019, and it wasn't particularly close.

What it tells us about 2020: The Padres are acutely aware that they're facing a tall task in the National League West. The Dodgers are the seven-time defending division champs, and they're favorites to make it eight. But San Diego played the Dodgers noticeably tougher in 2019. The Padres will be looking to close the gap in the standings significantly in 2020.

2. Paddack becomes the Sheriff
May 6 vs. Mets

A night after Renfroe's heroics, Paddack announced his presence on the national stage. Prior to the game, the Padres rookie had called out Mets rookie first baseman Pete Alonso, saying he believed voters had made a mistake in selecting Alonso as the NL Rookie of the Month. Paddack's words caused quite a stir. But he backed them up on the mound with 7 2/3 brilliant innings, striking out 11. Alonso went 0-for-4 and whiffed three times. The Padres won, 4-0.

What it tells us about 2020: The Padres might have a budding ace on their staff. Paddack's self-assured nature and his brazen approach to competition might rub some people the wrong way. But not in the Padres' clubhouse. Paddack finished with a 3.33 ERA and a sub-1 WHIP while pitching on an innings limit in 2019. He will be turned loose in '20, and his future is clearly bright.

3. A rally in the Rockies
June 14 vs. Rockies

The Padres trailed, 11-5, and their win expectancy stood at 0.8 percent when Tatis strode to the plate leading off the ninth inning. He smacked a single to left, sparking one of the most unbelievable comebacks in franchise history. As if to bring everything full circle, it was Tatis who capped the rally with a laser-beam single to center field, tying the game at 11. The Padres would score five runs in the 12th, en route to a 16-12 victory over the Rockies.

What it tells us about 2020: Tatis is the top-of-the-lineup spark that was absent in San Diego for a long time. He's persistent at the plate and never an easy out. Surely it's no coincidence that when he went down with a back injury in mid-August, San Diego began its spiral toward the bottom of the West. If the Padres are to emerge as a contender in 2020, Tatis will almost certainly be at the forefront.

4. The future shines bright
June 29 vs. Cardinals

A remarkable yellowy-orange-reddish-purple sky hung over a sold out Petco Park in late June. The Padres offered a performance to match it. Machado launched homers in consecutive at-bats. Tatis put his five-tool ability on full display, homering and scoring from second on a routine grounder. Paddack stifled a Cardinals team that would become NL Central champs. The Padres won 12-2 and finished that night 42-40 and a game out of the NL Wild Card race. For the first time in nearly a decade, fans could dream of playoff baseball in the East Village.

What it tells us about 2020: In retrospect, that was the season’s high point. The Padres would drop five straight and were never above .500 again. But that night still represents the entirety of the Padres' vision. They'd built the sport's best farm system, and it had finally begun to show. Plus, they'd complemented that farm system by investing in a superstar like Machado. The atmosphere at Petco Park was as lively as it had been in years. If (or perhaps when) the Padres establish themselves as contenders, this is what it will look like (though maybe minus the sunset).

5. Tatis arrives in style
March 28 vs. Giants

Petco Park gave Machado a rousing ovation before his Padres debut, and rightfully so. Machado, one of the offseason's most coveted free agents, had just signed a record-setting contract to play in San Diego. Then, a few moments later, that reaction was matched -- if not exceeded -- by a rookie shortstop. Such was the hype for Tatis, arguably the top prospect in the sport. And he didn't disappoint. Tatis singled through the left side off Madison Bumgarner in his first at-bat of the Padres’ 2-0 victory over the Giants. Then he dropped a bunt single toward third for his second big league hit.

What it tells us about 2020: It was pretty clear from the start: If he can remain healthy, Tatis has the makings of a superstar. At age 20, he posted a .317/.379/.590 slash line, and he'd have been a threat to become the youngest batting champ in history if not for a mid-August back injury. Tatis also ran the bases with a calculated audacity that made him one of the biggest baserunning threats in the Majors. He dazzled defensively, too. The Padres spent about a decade searching for their long-term answer at shortstop. They appear to have found that answer.