As Rudy Giuliani enters the center ring of the legal fight between President Donald Trump and special counsel Robert Mueller, the former New York City mayor is already anticipating one possible battle – a subpoena for President Trump to testify. “I think it’s 50/50,” Giuliani, the president’s personal attorney, told ABC News regarding the possibility of a subpoena. “But I got to prepare for that 50 percent.”

As ABC News confirmed earlier this week, the president’s legal team was told by Mueller he could “compel” the president to testify before a grand jury via a subpoena. As Ty Cobb steps down from his position as White House counsel handling the Russia probe for the presidency, his replacement, Emmet Flood, has been through battles like this before. “I think Emmet was brought in because he represented Clinton during their subpoena battle and knows a great deal about it,” Giuliani said.

Giuliani already believes he’s settled one case. The mayor argues that with the information now out about how the president reimbursed Michael Cohen for his payments to porn star Stormy Daniels, that case no longer has implications that campaign finance laws were violated.

“I think the investigation with him [Cohen] largely fell apart, with the loss of the campaign finance possible violation which never existed in the first place, but they sure thought it did,” Giuliani told ABC News Thursday night in a phone interview, adding that his client, President Trump, has nothing to worry about in this matter.