His rival, Volodymyr Zelensky, had made clear beforehand that he would not attend the debate because of a quarrel over timing. But the president, struggling to revive his flagging re-election campaign, went ahead anyway, assailing his opponent as an unserious “virtual candidate.”

The one-man “debate,” held in a stadium complex in Kiev, the capital, and broadcast live on television, came just a week before the second and decisive round of an election that has been dominated from the start by theatrical stunts and dirty tricks rather than policy issues such as how to settle a 5-year-old war in the east of the country.

Poroshenko, 53, speaking with journalists invited to the event, seized on Zelensky’s absence to press his campaign pitch that voters should not trust Ukraine’s future to an untested comic at a time of war. Zelensky, 41, has never held office, and has no political experience — aside from a television role in which his character, a teacher, accidentally becomes president.

“I don’t like it when instead of participating in debate we have a virtual candidate who wants to convince us only through videos,” Poroshenko, a candy tycoon, said of Zelensky. “It is not worthy of Ukrainian democracy.”

Noting that the president commands the armed forces and does not hold just a ceremonial position, he derided Zelensky, saying he was treating the election like “a plot from the movies.”

Hundreds of the president’s supporters gathered outside the stadium, waving Ukrainian flags and cheering his mocking of Zelensky, who has said he is ready to debate, but not until Friday. The runoff election is Sunday.

Poroshenko, who was elected after street protests in 2014 toppled Ukraine’s deeply corrupt leader, Viktor Yanukovych, has struggled to win over voters, besieged by accusations of corruption from some of his close friends and political allies.

Many Ukrainians are angry and disappointed over the dashing of hopes raised by their country’s so-called Revolution of Dignity in 2014. This has made it difficult for Poroshenko to win traction for his argument that electing Zelensky would play into the hands of President Vladimir Putin of Russia.

In the first round of voting in late March, Zelensky won far more votes than Poroshenko and more than 30 other candidates. Since then, opinion polls have shown him far ahead of the president.

This article originally appeared in The New York Times.