MESA, Ariz. -- One of the few downsides to all of the success the Chicago Cubs have had recently is that there aren’t many unknown quantities for fans to discover during spring training. But before you get to the middle of Chicago’s star-laden lineup, there exists a possible sleeper for the top spot of the order -- and he has been hard to miss so far this spring.

Switch-hitting second-year man Ian Happ wasn’t drafted in the first round of the 2015 draft to hit leadoff or play center field, necessarily, but that’s exactly what he has been doing during an eye-opening stretch of Cactus League play. If spring training is any indication, the seeds are being planted for manager Joe Maddon to grow the former Cincinnati Bearcat from a part-time piece to the primary guy as the leadoff hitter in Chicago’s 2018 lineup.

Ian Happ has homered four times this spring, twice from each side of the plate. Rick Scuteri/USA TODAY Sports

“I’m more comfortable, no doubt,” Happ said early in camp. “I know what to expect.”

After Happ hit 24 home runs as a part-time player last year, his apprenticeship seems to be over. Maddon has him batting first most often this spring, and he has responded. Going into Friday’s Cactus League action, Happ is 9-for-21 with a .500 on-base percentage and four home runs, two coming left-handed and two coming right-handed, and two of the four have led off a game.

Spring stats are hardly telling, but the Cubs haven’t had that kind of dynamism at the top of the order since Dexter Fowler left after the 2016 World Series. Happ is soaking in everything he can about the spot in the order where the Cubs ranked 12th in the National League in batting average and 10th in on-base percentage last year.

“My thought process going in is, it’s no different than anywhere else, I’m just going to get more at-bats,” Happ said. “It’s a different perspective knowing you’re going to get five at-bats as opposed to three to four.

“To be the best you can be that day, you want to be on base at least twice in five at-bats. Middle order or back order, you’re not really looking at it that way. At the top, if you get on once, you didn’t really do your job. Twice is a good day. More than that is great.”

In other words, it’s a mindset: Don’t change your swing or your style at the plate, but do change your mentality.

That’s what Happ has learned. And from whom did he learn it?

“You have to pick guys' brains,” Happ said. “I keep getting back to Dexter. He was always trying to get on base twice. It doesn’t matter how you do it.”

The word you hear most from scouts who have seen Happ for half a season in the majors is "athlete." Yes, he’s still raw -- especially in the outfield -- but it doesn’t take long to see his hand-eye coordination as well as his speed.

“The thing that stands out is his power,” one NL scout said. “It’s hard to see that coming from his frame. He needs work on his baserunning, but he looks fast.”

Happ is listed at 6 feet and 200 pounds, but those might be generous numbers. He packs a wallop, though. In the Cubs’ third spring game, he worked the count against Madison Bumgarner, then hit a 3-2 pitch out to right field. His two home runs hitting right-handed this spring are only three fewer than he hit from that side all last season, and a switch-hitting leadoff man with power at the top could make an already stacked Cubs lineup even more dangerous.

Happ isn’t slated to play every day, but it’s looking more and more as if he might bat first when he is in the lineup. A season-long debate revolved around what batting first did to Kyle Schwarber in 2017: Did it change a young hitter’s mindset too much? Schwarber has a keen eye and still struggled in the role, and Happ will have to eliminate some swing-and-miss from his game to succeed -- his strikeout rate was 31 percent, and his strikeouts-to-walk ratio wasn’t pretty at 3.31 -- but he’s just learning the league and himself.

One of Maddon’s concerns about players at the top of the order is the number they see on the scoreboard. An 0-for-5 day, as opposed to 0-for-3 or 0-for-4, can really hurt a batting average -- and an ego. That’s why taking some walks at the top of the order is important, for the team and the player. It kind of limits the exposure to a failed day.

“I know it’s going to even out over the course of the season, but your goal as a leadoff hitter is to get on base as much as possible for the big boys behind you,” Happ said. “You don’t put pressure on yourself or overthink it, but you just know going in you’re going to get that extra at-bat. If you don’t come to terms with it early, it’s going to eat you up.”

Happ won’t be 24 until August, but he already understands what the leadoff process is all about -- and what it’s not.

“I’m going to attack the baseball the same way,” he said. “I can’t change who I am as a hitter. I’m going to continue to be aggressive and take my walks when they come.”