Under 4.5 in soccer betting means you are wagering there will be four goals or fewer combined between the two teams in a match.
A prime example of a soccer over/under total betting line came from a match in the English Premier League this past spring when Manchester City made the trip to London to take on Fulham.
Manchester City had been scoring a lot of goals in the league, while Fulham had allowed a record number of goals up to that point of the year, so oddsmakers set the over/under for total goals at 4.5, anticipating plenty of fireworks.
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