Wendlinger had crashed heavily in practice for the previous year's Monaco Grand Prix, sustaining a serious head injury from which it took the rest of the season for him to recover. Since rejoining Sauber at the beginning of the current season, he had struggled to match his pre-accident form, lapping several seconds per lap slower than teammate Heinz-Harald Frentzen in the first four Grands Prix. Sauber released a statement clarifying that Wendlinger had not been sacked, and that he would still test for the team with a view to improving his performance. Boullion, who made his Formula One début as a result, was loaned to Sauber by Frank Williams, who was keen to use the known quantity of his test driver to evaluate Frentzen's potential for a future race seat in his team. Frentzen was in his second season of Formula One, but this event also marked his first race start at Monaco, as Sauber had withdrawn him from the previous year's race after Wendlinger's accident.