David Itskowitch, who helped launch the boxing division of Jay Z’s Roc Nation Sports almost two years ago, resigned as the company’s chief operating officer on Thursday.

Itskowitch was the first person hired by the fledgling promoter when it got into the boxing business in August 2014. Under his watch, Roc Nation Sports has put on a handful of cards, signed two of boxing’s biggest names in undefeated former super middleweight world champion Andre Ward and former four-division world titleholder Miguel Cotto, and promoted the second-biggest pay-per-view card of 2015, Cotto’s middleweight world title loss to Canelo Alvarez in November. That fight, which Roc Nation Sports co-promoted with Golden Boy Promotions, generated about 900,000 buys. Only the record-breaking Floyd Mayweather-Manny Pacquiao spectacle did more business.

Itskowitch did not give a reason for his resignation but said the parting was amicable.

“I’m appreciative of the opportunity that Roc Nation Sports gave me to build their boxing division,” Itskowitch told ESPN.com. “I value the relationships that I formed while I was with the company, and I am extremely proud of all that we accomplished in two years. I’m looking forward to new challenges in my career.”

Itskowitch, 41, said he was unsure if he would remain involved in the boxing business; it is the business he has been in for most of his adult life.

From 1996 to 2000, Itskowitch, of New York, worked at HBO as the right-hand man for then-senior vice president Lou DiBella, who was responsible for programming the network’s fights. When DiBella left HBO to found his own promotional company, Itskowitch went with him, working for DiBella Entertainment from 2000 to 2006.

Itskowitch then joined Golden Boy Promotions as its COO, working for Oscar De La Hoya’s company from 2007 until resigning in 2013 to take a break from the sport.

Roc Nation Sports plans to fill the COO position but probably not until after Ward’s fight against Alexander Brand on Aug. 6. “Roc Nation is thankful for the efforts and contributions Dave Itskowitch made to Roc Nation Sports, but at this time, we have decided to part ways,” Michael Yormark told ESPN.com. He is the president and chief of branding and strategy for parent company Roc Nation. “We wish him the best of luck in the future.”