Brad Keller was so good at Kauffman Stadium in 2020 that he didn’t seem to need the energy that Royals fans pack The K with every night.

But he’s sure excited to get that energy back.

“I kind of thrive off the energy, the adrenaline,” Keller said Monday before the Royals flew to Kansas City ahead of the regular season. “It helps me get through some of the tough parts of the game. I miss that and can’t wait to get it back.”

Keller is two days away from throwing the first pitch of the 2021 regular season, with around 10,000 fans allowed back in Kauffman Stadium for the first time in 18 months. Kansas City’s Opening Day starter for the second time, Keller posted a 0.27 ERA (one run in 33 innings) in five home starts last year, holding hitters to a .159 average and .385 OPS.

His complete game shutout on Sept. 13, 2020, against the Pirates -- when he struck out two and threw 111 pitches -- was the biggest moment he missed the crowd. Experiencing the ninth inning with fans on their feet is a feeling Keller hopes he can get in '21.

“I’ve never experienced a ninth inning before, I’ve never got the opportunity to go out there and pitch, so to get out there and finally get to the ninth inning, usually you have the lead and the fans are standing on their feet, clapping and cheering,” Keller said. “I wish I got that opportunity last year when I got out there, but hopefully this year, I’ll have another opportunity like that.”

Keller will look to take the next step as the Royals ace this year, with his second Opening Day nod (he couldn’t start Opening Day last season because of a COVID-19 infection) and further reinforcement that the Royals see him as their No. 1 starter -- as the player who leads on the mound and off it.

After throwing 54 2/3 innings in the pandemic-shortened 2020 season, Keller fully expects to exceed his 2019 workload of 165 1/3 innings this year. How that plays out is to be determined, with teams expected to be cautious with their young arms going into a 162-game season. But Keller wants to be a workhorse for the Royals, not only taking the ball every fifth day but going deep into games, too.

“I feel ready to go, I feel strong,” Keller said. “I feel like we’ve had a really good camp as far as weight training, running, conditioning, all that stuff. … Even having the weird season last year, I don’t think it’s been much of a change that we can see right now on our bodies.”

A Rule 5 Draft pick at the 2017 Winter Meetings, Keller made a quick rise in the Royals’ organization, from making the team and eventually the rotation in '18 to his first Opening Day start in '19, when he shut out the White Sox on two hits in seven innings. In three seasons with Kansas City, Keller has a 3.50 ERA over 78 games (57 games started). He’s not a high strikeout pitcher. Instead, his success comes from pounding the zone for early and weak contact. He relies heavily on his two fastballs -- a four-seamer that cuts and a two-seamer that sinks -- to go along with a slider and a changeup.

“He’s our ace for a reason,” third baseman Hunter Dozier said. “What he’s done the past two to three years is impressive. He’s fun to play behind. He works quick, he goes after hitters. He’s easy to play defense behind.”

Now three years into a Major League career and designated as the Royals’ No. 1 starter, Keller is approaching leader status, especially with the young pitchers on the horizon in the Kansas City farm system. But Keller is quick to tell you that he’s still learning from veteran starters like Danny Duffy and Mike Minor about how to be a leader in the clubhouse and from his pitching coaches about how to set an example on the mound.

His goal Thursday is to set the tone in a season full of optimism that the Royals can take the next step toward contending.

Even though he’s thrown the first pitch of a Royals season before, he doesn’t think the nerves will ever go away. He’ll stick to his normal routine, making sure to get a crossword puzzle done -- the USA Today crossword is his go-to, he says, mainly for the repeating clues -- before trying to regain the stoic nature he presents on the mound.

“It’s going to be exciting,” Keller said. “We’ve missed the fans. That’s been the talk this whole camp, finally getting back in front of our home fans back at The K. It’s going to be exhilarating. I can’t wait to get back out there.”