Susan Collins hasn’t decided whether to endorse or oppose President Donald Trump’s reelection bid. But she has reached a conclusion on his public performance during the coronavirus pandemic: “Very uneven.”

The Maine Republican senator, who is up for reelection herself this November, said in an interview on Tuesday that Trump has been effective when he’s focused on the coronavirus response and the recommendations of public health experts like Anthony Fauci, the top infectious disease expert in the U.S. But when he’s beefing with governors and journalists, far less so.

“It’s been very uneven. There are times when I think his message has been spot-on and he has really deferred to the public health officials who have been with him at these press conferences,” Collins said. “And then there are times when I think he’s been off-message and has brought up extraneous issues. So I think it’s been mixed.”