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Luke Bryan is catching some heat for checking lyrics written on his hand while he was singing the national anthem at Tuesday night's Major League Baseball All-Star Game.

Luke Tweets, "I had a few key words written down to ensure myself that I wouldn't mess up. I just wanted to do my best. I promise it was from the heart... If I offended anyone with my approach, I sincerely apologize. Anytime I sing the anthem it is an honor, and my heart beats out of my chest."

Luke adds that he did check his watch because he'd started late and the stealth bomber was flying over two minutes into the song.