MSNBC analyst Claire McCaskill said President Trump used "his fat thumbs" to try to intimidate former U.S. Ambassador to Ukraine Marie Yovanovitch in real time on Twitter during an analysis of the impeachment hearings Friday afternoon.

The comments came as Yovanovitch testified Friday that she felt threatened when she learned President Trump had brought up her service in Ukraine on a July call with the country's President Volodymyr Zelensky.

"I was shocked and devastated," she told the House Intelligence Committee. "It was a terrible moment."

"The president is not staying in the shadows for this bad act, but rather he's out there today with his fat thumbs tweeting to try to intimidate her real time," McCaskill told host Nicolle Wallace.

"I'm so proud of her," the former Missouri Democratic senator continued. "And every woman in America who has fought in a male-dominated career should cheer for this woman today; her guts, her accomplishments and the fact that she's the one that stood in their way."

Trump's tweet during Yovanovitch's testimony Friday morning asserted during the former ambassador's public testimony that she performed poorly throughout her career as a U.S. ambassador.

"Everywhere Marie Yovanovitch went turned bad. She started off in Somalia, how did that go? Then fast forward to Ukraine, where the new Ukrainian President spoke unfavorably about her in my second phone call with him. It is a U.S. President's absolute right to appoint ambassadors," Trump tweeted to his 65 million followers.