Late last year, the two veteran bankers teamed up to form RedBird Capital Partners, a private equity firm that would focus on control deals for growth-oriented companies, plus selective early-stage opportunities.

Cardinale was a longtime Goldman Sachs (GS) banker, where he was known primarily for sports deals like Goldman’s investment in YES Network and Alex Rodriguez’s absurd contract with the NY Yankees. Most recently he had spent a year in Chicago with Byron Trott’s BDT Capital. Rotman had co-founded Genuity Capital Markets in 2005, before merging it with Canaccord Financial Inc. (where he would serve as vice chairman of investment banking). The two previously had worked together on a Canadian media transaction, and reportedly were seeking $400 million for their debut fund.

Since then, RedBird has busted through its target. According to SEC filings, the firm already has secured nearly $618 million in capital commitments — including $500 million from an unidentified investor based outside the U.S. But Rotman is no longer listed on any of the documents.

No word yet on what triggered the departure, with one source simply saying that it “wasn’t a good fit.” That source adds that the fundraising effort is not yet concluded, although no word yet on what type of hard cap RedBird might have set.

With Rotman gone, Cardinale is now the sole owner of RedBird and managing member of its funds. But he does have some new investment help, hiring managing directors Hunter Carpenter and Robert Covington out of private investment firm The Stephens Group.

RedBird also has hired private equity veteran Thomas Mastrobuoni as chief financial officer and chief compliance officer.

To date, RedBird has made one deal: TierPoint (a.k.a. Cequel Data Centers), as part of an investor consortium that also includes The Stephens Group.

Cardinale has not yet responded to request for comment.

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