(Repeats item carried at the weekend)

* Ongoing spat between founders, board complicates CEO search

* External candidates are unlikely, analysts say

By Sankalp Phartiyal and Nivedita Bhattacharjee

MUMBAI/BENGALURU, Aug 19 (Reuters) - The dramatic departure of Vishal Sikka as chief executive of Infosys, following a months-long public battle with the tech giant's founders, has left the company with another messy problem: how to find someone willing to replace him.

With the boardroom row still simmering, the pressure will be on to do that fast.

The company's last CEO hunt in 2014 was a major challenge. Sikka, the eventual choice who was plucked from a top job at SAP , was the first chief appointed from outside the group of founders. His brief was to turn around a faltering business.

Three sources familiar with internal discussions three years ago said they expected an even tougher challenge now.

"It was extremely hard to find an external candidate last time, and the spat is going to make the job even more difficult now," said one of the sources.

"I think there is very little chance there will be an external candidate."

The new boss will be taking on a company in better shape than it was in 2014: Sikka has led efforts to diversify Infosys away from basic IT outsourcing services into more lucrative new areas, like cloud, automation and artificial intelligence.

Infosys' share price surged 22 percent between Aug. 1, 2014, when Sikka took office and Thursday, outperforming the broader Nifty IT index, which gained 6.3 percent in the period.

But his successor will also join during one of the most turbulent patches ever for the $150 billion Indian IT services sector. The industry is facing squeezed margins, Brexit question marks over European businesses, and uncertainty in the United States, thanks to visa policy changes.

Infosys' chairman, R Seshasayee, told reporters the company would not look for a major change in culture or strategy and was confident it could still attract talent.

"There may be some people who get excited by these kinds of challenging situations," said a senior Infosys source. "But anyone who is comfortable and doing well will think long and hard before taking this job."

The company has not publicly identified potential successors, though the interim chief executive Pravin Rao, CFO Ranganath D Mavinakere, deputy COO Ravi Kumar S and Mohit Joshi, the head of banking, financial and insurance services, are among the top internal candidates, according to the company source.

STAYING ON

In an unusual move, the board of India's No. 2 IT services company accepted Sikka's resignation, but named him executive vice chairman until a replacement was found. Rao reports to him.