used to describe a turning point in a situation. (For better or worse)
It only works when you say it dramatically, like some ESPN and Sports Analysts do.
It seemed the New England Patriots were going to win the super bowl, BUT THEN...Wes Welker dropped the ball.
It seemed The Heat were going to win the finals, BUT THEN...Dirk Nowvitzki scored 1,000 points.
It seemed that Yao Ming was going to be the last well known Asian in the NBA, BUT THEN...Jeremy Lin came along.
alternative for however
or just our well used but
i didn't like the food what they served at the restaurant.but then the waitress was cool n pleasant which was in fact,the only relief.