For sports fans, there’s a lot going on today. Lance Armstrong is in the lead in his final Tour de France. Tiger Woods is in the lead at the British Open. Teenager Michelle Wie is rolling through the men’s U.S. Amateur Public Links championship, with a Masters invitation on the line. The World Series of Poker is down to the final table, nine men guaranteed to win at $1 million each. The Yankees are playing the Red Sox. But nothing is bigger than this morning’s British Open round for Jack Nicklaus, who needs a huge round at the Old Course at St. Andrews to reach the weekend. Most likely, the competitive career of golf’s greatest player ends sometime this afternoon on golf’s most famous course at its original major championship. It should play out live on TNT (Channel 26 on Time Warner Cable), or follow the scores here.