By Chad Finn, Boston.com Staff

LONDON -- Welcome to Day 16 of competition, the penultimate day of the London Games and yet one of the biggest days in terms of total medals being awarded. Fifteen different sports will distribute gold, silver and bronze Saturday, including eight in athletics alone.

Saturday's must-see event: Bolt. There's probably no need to elaborate beyond the most famous and appropriate surname of these Games, but perhaps a reminder is needed that the 4x100-meter relay will not only be Jamaican sprinter Usain Bolt's final event of London, but there's a chance it's the 27-year-old's final Olympic appearance. He is expected to run the anchor leg for favored Jamaica. One more gold and one more electric moment seems like something he'll be able to conjure up.

Also worth watching: The official term for it is the women's Olympic basketball gold medal game. I prefer calling it the UConn Alumni Game better. Team USA, which is coached by Geno Auriemma and features four Huskies legends (Maya Moore, Diana Taurasi, Sue Bird, and Swin Cash) as well as the likes of Candace Parker and Tina Charles, takes on France with the gold medal at stake. History suggests it's a formality for Team USA, which is going for its fifth consecutive Olympic gold medal and 41st straight victory.

Friday's big story: No botched handoffs. No mishaps. Just blazing leg after blazing leg, until the US women's 4x100-meter relay team had overcome its odd recent history and shattered a 27-year-old world record in the event.

It was Carmelita Jeter who ran the anchor leg as the US completed the event in 40.82 seconds, more than a full half-second faster than the dubious standard set by East Germany in 1985. It was the first time the US had won the event since 1996, notoriously fumbling the baton both in 2004 and 2008 when they were among the favorites.

“I was thinking Olympic record, and when I saw world record I said, ‘Oh gosh,’ ” said Allyson Felix, who ran the second leg. “This is crazy.”

Tweet of the day: "WORLD RECORD, IT FELT AMAZING." -- @CarmelitaJeter, after the women's 4x100-meter relay.

Mind the gap, and stick around right here for further updates throughout the day.