Oracle Corp. co-Chief Executive Mark Hurd is taking a leave of absence from the company for health reasons, and his duties will be assumed by co-CEO Safra Catz and Oracle co-founder and Chief Technology Officer Larry Ellison.

In a note to employees today, Hurd (pictured) said he’d requested time off to focus on his health. Neither he or the company mentioned the specific health issues he is facing, nor did they say how long he might be gone.

“As you all know, Larry, Safra and I have worked together as a strong team, and I have great confidence that they and the entire executive management team will do a terrific job executing the exciting plans we will showcase at the upcoming OpenWorld,” Hurd said in the note.

It may have been that Hurd’s decision to take time off was made rather suddenly, since he was among several company executives scheduled to speak at Oracle’s OpenWorld event in San Francisco next week.

Hurd’s absence leaves Catz as Oracle’s sole CEO. The two executives have shared the role since 2014, when previous CEO Ellison announced he was stepping down from that position.

Oracle’s unusual leadership structure should at least ensure that the company won’t suffer too much from Hurd’s absence, said analyst Charles King of Pund-IT Inc.

“Safra Catz is a terrifically smart and able executive with deep experience in and understanding of Oracle’s business,” he said.

But another analyst disagreed, saying Hurd’s departure would be a huge blow for Oracle.

“Hurd is the de facto leader of the company and his shoes will be very hard to fill,” Patrick Moorhead of Moor Insights & Strategy told SiliconANGLE. “Very rarely do executives who make these kind of announcements return, and I believe Catz will be the solo CEO.”

Holger Mueller, principal analyst and vice president of Constellation Research Inc. added that the timing of Hurd’s departure was definitely unfortunate, what with it being so close to OpenWorld. Still, he said Oracle has a deep bench that should help to ensure a limited impact on the company’s performance in the short-term, at least

“Few tech companies have that depth at the top,” Mueller said, referring to Catz and Ellison. “We saw this earlier when Thomas Kurian left and his direct subordinates carried the load, while Ellison got to spend more time doing what he has fun with, namely product reviews.”

Oracle also announced its fiscal first-quarter results today, a day ahead of schedule. The company reported a profit before certain costs such as stock compensation of 81 cents per share on revenue of $9.2 billion.

The results were in line with expectations. Wall Street had forecast a profit of 81 cents per share on revenue of $9.29 billion.

Guidance for the next quarter came in light, however. Catz told analysts the company is looking at a second-quarter profit of between 87 and 89 cents per share. Wall Street had earlier forecast earnings in the range of 91 cents per share.

Oracle’s shares bounced around a bit in the aftermath of its earnings call. The stock initially fell about 5% in the after-hours trading session before recovering those losses.

Oracle’s cloud business was a bright spot in the quarter, with revenue from the cloud services and license support division – the company’s largest – growing 3% to $6.81 billion. That compares with overall revenue growth of less than a percentage point.

King told SiliconANGLE that the slight growth in Oracle’s cloud business was good news but that it “continues to lag behind the market leaders with whom it claims to be on par.”

Ellison in a conference call highlighted the strong performance of the company’s cloud enterprise resource planning business, which includes its Fusion ERP and NetSuite ERP products. Revenue there grew more than 33% in the quarter, and the company now counts more than 6,500 Fusion ERP customers and 18,000 NetSuite ERP customers, Ellison said.

In the call, Ellison told analysts that Oracle and SAP SE account for around half of the entire enterprise ERP market, but insisted that its main rival “does not have a true cloud system.” Ellison further claimed that Oracle was succeeding in its efforts to win some important customers away from SAP.

“Now we’re seeing some of [SAP’s] medium-large companies go ahead and pick us,” he said on the call.

Elsewhere, Ellison said, Oracle managed to add 500 new autonomous database cloud customers during the quarter. He said that figure should double in the next quarter. And more autonomous cloud services will be announced at OpenWorld next week, he said.

In another important development, Oracle said it was boosting its share buyback program by $15 billion, adding to almost $50 billion worth of stock that has been repurchased in the last 18 months.

Wikibon Chief Analysr Dave Vellante provided this breaking analysis of Oracle’s earnings and what’s coming next:

Photo: decayellen5243/Flickr