"Whenever I used to make the first-team roster, I was so happy that I'd call my wife and just laugh through the whole conversation. And then I'd go hitless at the plate and not say a word at home," Kim recalled during an interview on Wednesday. "But now, I don't get on these emotional roller coasters. Even if I fail today, I keep my head down and get ready for tomorrow. My wife thinks I am a completely different person now."

Kim broke out in 2016 with career highs of 37 home runs and 124 RBIs, both good for third place in the KBO. The following year, Kim appeared in all 144 games and batted a career-best .340, while launching 35 home runs and knocking in 115 runs.

Kim is in the midst of his best offensive season in 2018, with a .349 batting average, 44 home runs and 132 RBIs through 131 games.

Kim leads the league in home runs and RBIs, along with total bases (345) and hits (175). He's also near the top in runs scored, on-base percentage and slugging percentage.

With 103 runs scored this year, Kim is also the first KBO player to put up 30 homers, 100 RBIs and 100 runs in three consecutive seasons.

And Kim has been doing this for the club that clinched the best regular season record on Tuesday and is an odds-on favorite to win a third title in four seasons. As the best hitter on the best offensive team in the league, Kim will receive serious MVP consideration.

That's some heady stuff for the one-time catching prospect.

Kim was drafted as a catcher in 2008 but was limited to 14 games that year. He completed his mandatory military service and rejoined the Bears in 2011, and started taking fielding practices at both first base and in the outfield.

With established catchers in the system, the Bears wanted to keep Kim's bat in the lineup by moving him to a new defensive position. But Kim's woes at the plate continued over the next few seasons as he split time between the KBO and its minor league, the Futures League.

Kim finally got some regular playing time in 2016 and burst out with his first 30-100-100 season in home runs, RBIs and runs.

And just before that turnaround season, Kim enjoyed a personal milestone, as he became a father of twin daughters in November 2015.

"I try to spend as much time with them as possible, and I think I've developed some patience in the process," Kim said with a smile. "As a father, I've felt all kinds of emotions."

Kim said he's determined to end this year feeling a different sort of emotion than last year. The Bears lost to the Kia Tigers in five games in the 2017 Korean Series -- the KBO's championship final -- but they look poised to return to the top in 2018.

"I hate losing more than ever, especially after last year's Korean Series," Kim said. "Before the start of the regular season, we didn't think we had enough talent to win a championship, but we were determined to work hard for it. We'll try to win the last game of the season." (Yonhap)