I do not remember that happening pre-vaccine.

Because there weren't deaths on a weekly basis.

I did a search for "Athlete deaths 2018"

This story from Aug. 2018 indicates:

Between 1997 and 2016, more than 11,000 players filled in a health questionnaire, and were given a physical examination, 12-lead ECG and electrocardiography. Of these players, 42 (0.38%) had cardiac diseases that could cause sudden cardiac death.

It only mentions two footballers (That shit ain't football to me), one died in 2003, and one in 2012.

This study indicates in a period of 20 years, there had been 8 sudden cardiac deaths.

Sudden Cardiac Deaths Table 3. Characteristics of Athletes with Sudden Cardiac Death.

Autopsy data were available for all sudden cardiac deaths. Among the athletes who died from cardiac disorders, the mean time between screening and sudden death was 6.8 years (range, 0.1 to 13.2). Cardiomyopathy were the most common cause of death and accounted for 7 of 8 (88%) sudden cardiac deaths (Table 3). There were a total of 118,351 person-years of follow-up over the 20-year study period. The resulting overall incidence of sudden cardiac death among adolescent soccer players was 1 per 14,794 person-years, or 6.8 per 100,000 athletes.

Wonder what that rate is now, especially give that those who died had previously been been screened as having no heart problems.