Joe Biden accidentally referred to his rival, Sen. Bernie Sanders, as “president” during the third Democrat primary debate on Thursday.

The former vice president, who has been besieged by a recent string of high profile gaffes on the campaign trail, made the comment while attempting to disparage Sanders and his signature Medicare for All proposal.

“If you notice, nobody’s yet said how much it’s going to cost the taxpayer. I hear this, large savings, the president,” Biden said of Sanders, before quickly correcting himself. “My friend from Vermont thinks that the employer is going to give back if you negotiate as a union all these years, got a cut in wages because you got insurance.”

The verbal misstep was not the first of the night for the 76-year-old Biden, who inadvertently referred to himself as “congressman” when discussing his support for criminal justice reform. Apart from mixing up titles, Biden has also exhibited a penchant for confusing time and place on the campaign trail.

One of the most worrying lapses came last month when Biden claimed to be vice president during the mass shooting at Marjory Stoneman Douglas High School in Parkland, Florida.

“Those kids in Parkland came up to see me when I was vice president,” Biden said before claiming that when the survivors visited Congress, lawmakers were “basically cowering, not wanting to see them. They did not want to face it on camera.”

Many were quick to point out that the tragic shooting, which resulted in 17 fatalities and more than a dozen injuries, actually occurred on February 14, 2018 — more than a year after Biden left office.