Complex sentence: On the opening game of the 2013 NFL season, Manning became one of only six players in NFL history to throw seven touchdowns in a game, doing so against the defending Super Bowl XLVII champions, the Baltimore Ravens.
Split into simpler sentences: On the opening game of the 2013 NFL season, Manning became one of only six players in NFL history to throw seven touchdowns in a game. He did so against the defending Super Bowl XLVII champions, the Baltimore Ravens.