Less than 48 hours after Wisconsin’s season-opening win over Illinois, quarterback Graham Mertz has reportedly testing positive for coronavirus.

That’s according to a report from Colten Bartholomew of Madison.com.

Per the report, Mertz tested positive with a daily rapid antigen test. Mertz will now undergo a nasal swab test to confirm the diagnosis.

If he does in fact have COVID-19, he will have to sit out for at least 21 days as per Big Ten policy.

Wisconsin’s next three games are at Nebraska, at home for Purdue and then at Michigan on Nov. 14.

Mertz threw for five touchdown passes in the Badgers’ win over the Illini.

He was starting in place of Jack Coan, who’s out indefinitely with a foot injury. If Mertz and Coan are both unavailable, sophomore Chase Wolf is next up on the depth chart.

This is one of the first COVID-19 incidents that the Big Ten has had to deal with in recent weeks. Purdue coach Jeff Brohm tested positive last week and missed the Boilermakers’ season-opener vs. Iowa.

If there are more positive tests within the Wisconsin locker room, here are the Big Ten’s guidelines for declaring a game no-contest:

There are categories (green, orange and red) associated with teams based on rolling seven-day averages. If a team positivity rate (number of positive tests divided by total number of tests administered) exceeds 5 percent or its population positivity rate (number of positive individuals divided by total population at risk) is more than 7.5 percent, the program can’t practice or play in a game for at least seven days.

Barring further positives at Wisconsin, the Badgers will play Nebraska on Saturday in its Week 2 matchup. Kickoff is slated for 3:30 p.m. ET.