Martina McBride showed up at the Resch Center in Green Bay, Wis. Saturday night with a heavy heart ... and an upset stomach. Most people can take to their bed, wrap themselves under their covers, and sleep off their bouts with viral or flu symptoms.

Martina is not most people! In the spirit of "the show must go on," the superstar performed in spite of her symptoms, telling concertgoers early in the evening that she'd been battling sickness for the last several days but didn't want to cancel on what was a near-sellout crowd.

According to the Green Bay Press Gazette, Martina wiped away tears as a crowd of 6,033 came to its feet in a loving and extended show of support after she pushed herself to pull off the soaring ballad 'Broken Wing.' The significance of the lyrics "And with a broken wing/She still sings," was not lost on her admirers.

"Oh man, you guys are killing me," she exclaimed, clasping her hands over her chest.

"It's a struggle up here for me tonight," Martina told the audience. 'On nights like this, we just cross our fingers and hope for the best. I promise I will sing my heart out for you tonight."

Martina dealt with frequent coughing bouts between songs and constant reaches for water, but the Gazette reports that "the effects on her actual performance were far less noticeable than probably even she realized.

"When you have one of the greatest voices in contemporary country, a Martina McBride at, say, 75 percent on this night still outshines most singers at 100 percent on any other night," reasoned the newspaper's reporter.

The "gutsy" performer "who refused to let her fans feel as if they were getting anything less than the best she could give," began her journey through some of her best work: 'Happy Girl,' 'Help Me Make it Through the Night,' and her trademark anthems 'Concrete Angel,' and 'This One's for the Girls,' and obviously made the evening an unforgettable experience for her fans, in spite of the challenge.

Martina's Shine All Night tour with Trace Adkins continues through May 2.

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