When the Major League Baseball season begins next week, fans who catch a homer or a foul may notice a new signature on the ball. It will read “Robert D. Manfred Jr.,” the most tangible sign that for the first time since 1992, baseball has a new commissioner.

But then, the ascension of Manfred as Bud Selig’s replacement in recent months has been hard to miss. Since taking over in January, Manfred has gone from a mostly behind-the-scenes power broker to an outspoken advocate for change—in the sort of measured, plodding way that baseball always changes.

The 56-year-old Manfred, who was formerly the league’s chief operating officer and longtime labor chief, has pushed initiatives to speed up the pace of play. And he has expressed an open-mindedness about seemingly radical moves, such as banning defensive shifts as a means of boosting offense.

In a recent interview with The Wall Street Journal, Manfred discussed a range of issues confronting the sport. Below are edited excerpts from the interview.

WSJ: Do you want to see more offense?