Jim Harbaugh knows a thing or two about toughness.

This is the coach, after all, who wanted so badly to join his players on the field that he once wiped one of his guys' blood on his face.

So when Harbaugh saw a fellow former University of Michigan student display impressive perseverance, he had to tweet at her. That woman was none other than Madonna.

The 56-year-old Queen of Pop, who was born in Michigan and briefly attended school in Ann Arbor, took a tumble last week during a performance at the BRIT Awards. True to her status as one of the best performers alive, Madonna got back up and continued with her set.

Here's the video:

Harbaugh, who may or may not be a fan of Madonna's music, sent out this tweet upon seeing the clip:

Toughness is a trait Harbaugh and his staff have emphasized since he took over at Michigan in December. Harbaugh said that in evaluating recruits, he was looking for players who showed a certain edge.

"How do you gauge somebody's toughness?" Harbaugh told reporters in February. "I mean, what does their contact courage look like? A back that will lower their pads going through a hole, a defender that cannot wait to get from point A to point B and go hit somebody. We wanted guys who are serious about football."

For someone who managed to stay off Twitter for a while, Harbaugh appears to have taken a liking to the social media platform. Since joining in January, he's tweeted practically every day, mostly with motivational slogans and shout outs to people (like Madonna) who inspire him.

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