The laser tag place that Saul tries to get Walter to use as a money laundering business in Abiquiu (2010) - Hinkle Lazer Base - is one of the job advertisements in the newspaper that Jimmy is reading through in the beginning.
The Albuquerque Isotopes are a real minor leagues team; however, the name is based on a fake one. In The Simpsons (1989), the Isotopes were Springfield's local team and property of Duff Breweries, who was going to move the team to Albuquerque much to the town's dismay. The year after the episode came out the city voted to make the Isotopes their new team's new name.
The office argument about who would win in a fight, Muhammad Ali or Bruce Lee, was in the controversial Bruce Lee scene in Once Upon a Time... in Hollywood (2019). In the movie, the character of Bruce Lee is bragging about being able to beat Muhammad Ali.
When Jimmy gets up to feed the fish, make coffee and look for work in the paper, the jazzy piano tune playing is "The Shadow of Your Smile".
Baseball catcher Keith McDonald is mentioned by the announcer during the minor league game Mike is watching. At the time the game was played, McDonald would have been a former St. Louis Cardinal, having played for the team in 2000 and 2001. McDonald has the distinction of being the sole National League player--and the second in baseball history (the first was Bob Nieman for the 1951 St. Louis Browns)--to hit a home run in his first two major league at-bats (baseball-almanac.com, baseball-reference.com, Wikipedia). McDonald is the only major league player to have three home runs--all three in the 2000 season with St. Louis--but no other hits for his entire MLB career (baseball-reference.com).