He played college football at Iowa State, initially signed by the Jacksonville Jaguars as an undrafted free agent in 2018.

[2] Lazard has been selected to the First-team All-Big 12 in both 2016[3] and 2017[4] and is Iowa State's career leader in both receptions[5] and receiving yards.

[7] Lazard built on the success from his freshman season by starting all 11 games he played in and led the team in receptions (56), receiving yards (808) and touchdown catches (6).

[24] Lazard was named Second-team All-Big 12 by the AP[25] and ESPN's Big 12 All-Underclassman team for second-straight season as well receiving the Pete Taylor Most Valuable Player.

[35] Lazard was named First-team All-Big 12 by the Coaches[3] and ESPN[36] and as the Pete Taylor Most Valuable Player for the second straight year.

[53] Lazard recorded his first professional touchdown, a 35-yard reception from Aaron Rodgers, during a Week 6 win over the Detroit Lions on October 14, 2019.

[54] He had a breakout performance on December 1, 2019, in a 31–13 Week 13 victory over the New York Giants, posting three catches for 103 yards and a touchdown.

[58] In the season-opener against the Minnesota Vikings, Lazard caught four passes for 63 yards and his first touchdown of the season during the 43–34 road victory.

[59] During Sunday Night Football against the New Orleans Saints in Week 3, Lazard finished with six receptions for 146 yards and a touchdown in the 37–30 road victory.

[62] In Week 12, in his second game off of injured reserve, Lazard caught his third touchdown of the season in a 41–25 victory over the Chicago Bears, along with 23 receiving yards.

Lazard finished the season with 33 receptions for 451 yards and three touchdowns, nearly matching his previous year total despite playing in six fewer games.

[63] In the Divisional Round of the playoffs against the Los Angeles Rams, Lazard recorded four catches for 96 yards, including a 58-yard touchdown, during the 32–18 win.

On October 26, ahead of the Packers' Week 9 game against the Arizona Cardinals, fellow wide receiver Davante Adams tested positive for COVID-19.

In Week 16, in a Christmas Day showdown with the Cleveland Browns, Lazard caught Rodgers' 443rd career touchdown pass with the Packers, breaking the previous record of 442, held by Brett Favre.

[71] The following week, he caught all six of his targets for 72 yards and a touchdown as the Packers won 37–10 against the Vikings to clinch home-field advantage throughout the playoffs.

His five touchdowns over the final five weeks of the season were tied for second most in the NFL over that time span, second only to teammate Davante Adams.

Despite dropping a crucial pass during the game's opening drive, Lazard finished with two touchdowns during the 32–19 loss to the San Francisco 49ers.