Twitter index: Federer advances at Australian Open, Ravens headed to Super Bowl

In second place among Twitter's worldwide trending topics is Swiss tennis player Roger Federer, who beat Canadian player Milos Raonic in straight sets at the Australian Open. Federer will next go up against Jo-Wilfried Tsonga in the quarter-finals at Melbourne Park.

The current third- and fourth-place trending topics, meanwhile, relate to the Super Bowl, which will pit the Baltimore Ravens against the San Francisco 49ers on February 3. The Ravens beat the New England Patriots, whose quarterback, Tom Brady, is also a trending topic, to win the AFC Championship and advance to the Super Bowl.

Yet more sports talk is putting "Lebron" and "Kings" in ninth and tenth place. The NBA is reportedly moving the Sacramento Kings to Seattle, and Miami Heat player LeBron James (@KingJames) reacted to the news with a series of tweets, including the most recent: "I do know Mayor Johnson and the city/fans of Sacramento will do whatever it takes to keep the team put. We'll see what happens."

The top 10 most talked about topics on Twitter on January 21 at 1:45 pm GMT are:

• #quote
• Federer
• Jeremy Kyle
• Ravens
• Patriots
• #ConfessionNight
• Britney Spears
• Tom Brady
• Lebron
• Kings