Question: What company's advertising mascot was the precursor to the dog that debuted in a Bud Light Super Bowl XXI ad in 1987?

Context paragraphs:
Alex the Dog: Alex the Dog was the advertising mascot for Stroh's beer in the 1980s and precursor to Budweiser's Spuds MacKenzie.  At the peak of his career, Alex appeared in parades, on "Good Morning America", and the "Today" show.  He even inspired a series of toys, posters, cologne, shampoo and hand lotion.  Hip-hop artist Tone Loc referenced Alex the Dog in his song "Funky Cold Medina".

1986 New York Giants season: The 1986 New York Giants season was one of the most successful seasons in the professional football franchise's history.  The New York Giants, who play in the National Football Conference (NFC) of the National Football League (NFL), won their fifth championship—and first Super Bowl—in franchise history during the season.  Led by consensus league Most Valuable Player (MVP) linebacker Lawrence Taylor and Super Bowl MVP quarterback Phil Simms, the Giants posted a 14–2 record during the regular season, tied for the best record in the league with the defending Super Bowl champion Chicago Bears and the best in team history.  The Giants improved on their 10–6 record from 1985, won their first division championship since the NFL-AFL merger in 1970, and won Super Bowl XXI against the Denver Broncos.

Robbie Jones (American football): Robert Washington Jones (born December 25, 1959) is a former American football linebacker.  He played five seasons for the New York Giants.  He was Special Teams Captain of the 1986 Giants team that won Super Bowl XXI.  For his play during the Super Bowl year, Jones was awarded Special Teams Player of the Year by the Giants organization and also named the Special Teams Captain during the 1986 Super Bowl campaign.

Spuds MacKenzie: Spuds MacKenzie is a fictional dog character created for use in an extensive advertising campaign marketing Bud Light beer in the late 1980s.  The Spuds MacKenzie mascot and campaign were created by a 23-year-old art director, Jon Moore.  At the time he was working at Needham, Harper & Steers, a Chicago, Illinois, advertising agency.  The dog first showed up in a Bud Light Super Bowl XXI ad in 1987.  During the height of his popularity, large amounts of Spuds merchandise was available, such as plush toys and t-shirts.

Super Bowl XXI: Super Bowl XXI was an American football game between the American Football Conference (AFC) champion Denver Broncos and the National Football Conference (NFC) champion New York Giants to decide the National Football League (NFL) champion for the 1986 season.  The Giants defeated the Broncos by the score of 39–20, winning their first ever Super Bowl, and their first NFL title since 1956.  The game was played on January 25, 1987, at the Rose Bowl in Pasadena, California.

1986 NFL season: The 1986 NFL season was the 67th regular season of the National Football League.  The defending Super Bowl Champion Chicago Bears shared the league's best record with the Giants at 14-2, with the Giants claiming the spot in the NFC by tiebreakers.  In the AFC, the Cleveland Browns earned home-field advantage with a record of 12-4, and they hosted the New York Jets in round one of the AFC playoffs.  The Jets had started the season at 10-1 before losing their final five contests.  The game went to double OT, with the Browns finally prevailing 23-20.  The following Sunday, John Elway and the Denver Broncos defeated the Browns by an identical score in the game known as The Drive, where Elway drove his team 98 yards to send the game to overtime to win.  The Giants would defeat their rival Washington Redskins in the NFC title game, blanking them 17-0 to advance to their first Super Bowl.  The season ended with Super Bowl XXI when the New York Giants defeated the Denver Broncos 39-20 at the Rose Bowl to win their first league title in 30 years.

Jerry Markbreit: Jerry Markbreit (born March 23, 1935) is a former American football referee in the National Football League (NFL) for 23 seasons and became one of the most recognizable referees in the game.  Markbreit officiated football games for 43 seasons.  From 1965 to 1975, Markbreit officiated college football games in the Big Ten Conference.  He then joined the NFL in 1976 as a line judge before being promoted to the head referee position in just his second year.  His uniform number in the league was 9, which is now worn by Mark Perlman.  Until he retired from the NFL after the 1998 season, Markbreit officiated in two wild card (1991 and 1994), ten divisional (1979, 1981, 1982, 1985, 1986, 1987, 1988, 1995, 1997, and 1998), eight conference championship (1980, 1983, 1984, 1989, 1990, 1992, 1993, and 1996) playoff games, one Pro Bowl (1978), and four Super Bowls: Super Bowl XVII, Super Bowl XXI, Super Bowl XXVI, and Super Bowl XXIX and was an alternate in Super Bowl XIX, Super Bowl XXII, and Super Bowl XXVIII.  To date, he is the only NFL head referee to officiate four Super Bowl games.

Bud Bowl: The Bud Bowl was a stop motion animated Super Bowl advertising campaign first aired in 1989, and sporadically during the 1990s.  It served as an advertisement for Anheuser-Busch's Budweiser family of beers.  It featured anthropomorphized Budweiser bottles playing a football game against Bud Light bottles.

1991 New York Giants season: The 1991 New York Giants season was the 67th season for the club in the National Football League.  The Giants entered the season as the defending Super Bowl champion but failed to qualify for the playoffs.  They were the eighth team in NFL history to enter a season as the defending Super Bowl champion and miss the playoffs, and became the first organization in NFL history to do so twice; the Giants missed out on the playoffs a season after winning Super Bowl XXI as well.

Big Blue Wrecking Crew: The Big Blue Wrecking Crew was the defense for the New York Giants during the 1980s that won two Super Bowl Championships, the first in Super Bowl XXI in 1986 and the other in Super Bowl XXV in 1990.  A 3-4 defense, it was among the greatest NFL defenses of all time, and featured Lawrence Taylor as its star, considered by many to be the greatest defensive player in NFL history.

Supporting paragraphs: Alex the Dog Spuds MacKenzie
Answer: Stroh's