It was a freak accident. Testaverde was lunging forward in an attempt to recover a fumble by the running back Curtis Martin when he fell.
The loss of their leader, who threw 29 touchdowns and just seven interceptions a season ago, has already had a devastating effect on team morale. "He's irreplaceable. I don't know what the hell you're going to do," said the receiver, Keyshawn Johnson. "I never dreamed in a million years we would lose our starting quarterback in the first game of the season."
Despite a brave effort from his replacement, Tom Tupa, the Jets also lost the game in sickening fashion when the Patriots kicker, Adam Vinatieri, successfully converted a 23-yard field goal with just three seconds remaining.
The importance of having a quarterback of proven quality was confirmed by unlikely victories for the Green Bay Packers and Dallas Cowboys. Trailing by 21 points in the fourth quarter against the Washington Redskins, the Cowboys were revitalised by the brilliance of their passer, Troy Aikman, who tied the game with less than two minutes remaining with a touchdown pass to Michael Irvin.
Aikman then completed the job with a 76-yard strike to Raghib Ismail in overtime to complete a 41-35 triumph. He finished with 362 yards and five touchdowns, while the Redskins confirmed that they have retained their penchant for self-destruction.
Brett Favre was in similarly irresistible form for the Packers, who trailed the Oakland Raiders for most of the contest only for Favre to find the receiver Jeff Thomason for the game-winning score with just 11 seconds left. Favre threw four touchdowns in his side's 28-24 triumph.
The latest drama of the day occurred in Philadelphia, where the Eagles raced to a 21-point lead over the highly rated Arizona Cardinals but let it slip away in the second half. The Cardinal comeback was completed when the kicker Chris Jake sent over a 31-yard field goal with no time on the clock, giving Arizona their only lead of the game at 25-24.
An unexpected success came in St Louis, where the quarterback Kurt Warner, making his first NFL start, threw three touchdown passes as the Rams disposed of the Baltimore Ravens 27-10. Warner, whose only previous professional experience was with the Amsterdam Admirals in Europe, was pressed into service following the pre-season injury to Trent Green.
The big shock of the opening day was the San Francisco 49ers' humbling by Jacksonville Jaguars. San Francisco, the most consistent team of the last 20 years, have been hit by player losses and in-fighting between the team president, Bill Walsh, and the head coach, Steve Mariucci, and it showed in a 41-3 humiliation. The normally prolific quarterback, Steve Young, was held to just 96 yards, also giving up two interceptions.
The Minnesota Vikings gained a measure of revenge against the team who beat them in last year's playoffs, the Atlanta Falcons. Despite a late Atlanta rally, the Vikings held on for a 17-14 win.
It was all smiles and celebrations in Cleveland as the Browns returned to active duty for the first time since 1995. However, the smiles faded as Pittsburgh Steelers completed a 43-0 humbling that was every bit as convincing as the scoreline suggests.