In 2000, NBC declined to renew its broadcast agreement with Major League Baseball. In 2002, it was additionally outbid by ESPN and ABC for the NBA's new broadcast contract, ending the league's twelve-year run on NBC.
Former logo for NBC Sports, used from 1989 to 2011.
During this era, NBC experimented with broadcasting emerging sports. In 2001, the network partnered with the World Wrestling Federation (WWF) to establish the XFL - a new football league which introduced modified rules and debuted to tremendous, but short-lived fanfare, only lasting one season (NBC shared broadcast rights to the league's games, which were mainly held on Saturday nights, with UPN). In 2003, NBC obtained the broadcast rights and a minority interest in the Arena Football League. The network televised weekly games on a regional basis, as well as the entire playoffs. The deal lasted four years, after which the league and NBC parted ways.
Beginning with the 1999 Pennzoil 400, NBC began its foray into NASCAR. NBC, along with Fox, FX and TNT, obtained the broadcast rights of the top two series - the Winston Cup and Busch Series - in a six-year deal, beginning in 2001. NBC televised the second half of the season and alternated coverage of the Daytona 500 with Fox. In December 2005, NBC announced that it would not renew its agreement with NASCAR. In 2001, NBC obtained the broadcast rights to horse racing's Triple Crown in a five-year deal.
In 2004, NBC reached a broadcast agreement with the National Hockey League (NHL). The revenue-sharing deal called for the two sides to split advertising revenue after the network recouped the expenses. Games were supposed to begin airing on the network during the 2004-05 season, however a league lockout that resulted in the cancellation of that season delayed the start of the contract until the second half of the 2005-06 season. NBC televised regular season games at first on Saturday afternoons before moving the telecast to Sundays, Saturday and Sunday afternoon playoff games, and up to five games of the Stanley Cup Final. Additionally in 2008, NBC broadcast the first Winter Classic, an outdoor NHL game played on New Year's Day at Ralph Wilson Stadium, a success in attendance and television ratings. The following year's Winter Classic would become the most-watched regular season game in 34 years. In addition to this regular season success, Game 7 of the 2009 Stanley Cup Final was watched by an average of 8 million viewers, the highest ratings for an NHL game in 36 years.
In January 2011, Comcast finalized its acquisition of a majority share in NBC Universal. As a result of the merger, the operations of Comcast's existing sports networks, such as Golf Channel and Versus, were merged into an entity known as the NBC Sports Group. NBC Sports' senior vice president Mike McCarley additionally became Golf Channel's new head. NBC Sports' golf production unit was merged with Golf Channel, along with NBC's on-air staff, with that unit rebranding under the banner "Golf Channel on NBC", while Versus was reformatted toward a more mainstream audience, renamed the NBC Sports Network and eventually rebranded as NBCSN.
The merger also helped influence an extension of NBC Sports' contract with the NHL; the 10-year deal - valued at close to $2 billion, unified the cable and broadcast television rights to the league and introduced a new "Black Friday" Thanksgiving Showdown game on NBC, along with national coverage for every game in the Stanley Cup playoffs. On July 3, 2011, ESPN obtained the exclusive broadcast rights to Wimbledon in a 12-year deal, ending NBC's television relationship with The Championships after 42 years.
From 2012 until 2015, Major League Soccer games were shown on NBC and the NBC Sports Network. This included the broadcast of two regular season games, two playoff games, and two national team matches on NBC and 38 regular season games, three playoff games, and two national team matches on NBC Sports Network. Since the 2013-14 season NBC Sports has also held the rights to televise Premier League soccer in English (primarily on NBCSN) and Spanish (on Telemundo and mun2), through a $250 million deal, replacing ESPN and Fox Soccer as the league's U.S. broadcasters.
NASCAR returned to NBC Sports properties in 2015 under a ten-year deal, with NBC once again airing the second half of the NASCAR Cup Series and Xfinity Series seasons. While no specific financial details were disclosed, NBC reportedly paid 50% more than ESPN and TNT (who took over the portion of the season previously held by NBC) combined under the previous deal.
On June 7, 2015, NBC Sports and The R&A agreed to a twelve-year deal to televise The Open Championship, Senior Open Championship, and Women's British Open on NBC and Golf Channel, beginning in 2017. The move came a year after NBC lost the rights to USGA tournaments to Fox Sports but fox sports opted out after the 5th year of the deal therefore nbc picked up the rights for the remainder of the deal(which the deal lasts for 12 years) The R&A's deal with ESPN had been through 2017, but the broadcaster opted out of the final year of their agreement.
Universal Sports Network ceased operations in November 2015. NBCUniversal acquired the rights to the content that was previously held by Universal Sports Network. Much of the programming moved to Universal HD, with the rest of the programming moving to NBCSN and NBC Sports Live Extra.
In early 2018, it was announced that NBC Sports would renew its contract with the IndyCar Series (continuing a relationship with NBCSN which began in 2009 as Versus), through 2021, and acquire the broadcast television rights previously held by ABC. NBC televises eight races per-season since 2019, including the series flagship Indianapolis 500, with the remaining races airing on NBCSN as before. An IndyCar package is also offered through NBC Sports Gold. Shortly after, NBC announced a six-year agreement with the IMSA beginning 2019, including the WeatherTech SportsCar Championship, with the majority of coverage on NBCSN.
On June 29, 2020, NBC re-acquired the rights of the USGA Championships (U.S. Open, U.S. Women's Open, U.S. Amateur, U.S. Women's Amateur) from FOX Sports beginning with the 2020 U.S. Open. Under the arrangement of the original 12 year deal, NBC would carry the event until 2026 airing the later rounds while The Golf Channel would broadcast the early rounds in their entirety. 
In 1964, NBC televised the Summer Olympics in Tokyo; in 1972, NBC televised the Winter Olympic Games for the first time. 1980 would prove to be a stinging disappointment for the network; after contentious negotiations, NBC won the broadcast rights to the Summer Games in Moscow. After the Soviet Union invaded Afghanistan, the United States and 64 other countries boycotted the event. NBC substantially scaled back its coverage and lost heavily in advertising revenue. In 1988, NBC televised the Summer Olympics in Seoul. Since then, it has branded itself as "America's Olympic Network", televising every Summer Olympic Games since the Seoul event, as well as every Winter Olympics since 2002. In total, NBC has aired 13 Summer and Winter Olympics, the most by any one U.S. network. The Olympic Games have also become an integral part of the network, despite some recurring controversy over its method of tape delaying events in part to take advantage of a wider national audience in prime time.
In 1998, Ebersol was named president of NBC Sports and Olympics.
The 2010 Games in Vancouver were watched by a total of 190 million viewers, including 27.6 million viewers of the gold medal game in men's hockey.
During the 2014 Winter Olympics in Sochi, Russia, over 500 hours of the games were broadcast across five NBC-owned television channels (NBC, NBCSN, CNBC, MSNBC and USA Network), with 1,000 hours being streamed digitally. In January, the company announced some exclusive digital-only streaming of the 2014 Olympics via the NBCOlympics.com website and the NBC Sports Live Extra app for Android and iOS, including exclusive content such as Gold Zone, Olympic Ice and NBC's Olympic News Desk.
With the premiere of Sunday Night Football, NBCUniversal hired Troika Design Group to design an overall visual identity for its coverage, including branding, on-air graphics, and other visual elements.
Concurrent with the relaunch of Versus as NBC Sports Network on January 2, 2012, and the 2012 NHL Winter Classic, NBC Sports also launched a comprehensive redesign of its branding, including a new on-air graphics design built around the NBC peacock, and an updated logo for the division as a whole (replacing a logo that had been in use since 1989). The new design was also intended to be modular, allowing it to be expanded for use in larger events across multiple networks (such as the Super Bowl and the Olympic Games). A refreshed design for on-air graphics was introduced on January 1, 2015 (in time for the 2015 NHL Winter Classic and NFL playoffs), with a cleaner and brighter visual appearance.
NBC debuted a new graphics package specifically for Sunday Night Football during Super Bowl LII. NBC producer Fred Gaudelli stated that the network wanted the Sunday night games to have a more distinctive presentation to set them apart from other games. NBC similarly diverged for its Premier League coverage in 2019, adopting elements of its new British sibling Sky Sports.