For the first time in franchise history, the Mariners play a home game outdoors. Under an open retractable roof, Seattle’s debut at the $517.6 million Safeco Field becomes forgettable as closer Jose Mesa squanders a 9th-inning lead by walking four batters, resulting in a 3 – 2 defeat to the Padres. A crowd of 44,607 is on hand.

On July 15, 1999 For the first time in franchise history, the Mariners play a home game outdoors. Under an open retractable roof, Seattle’s debut at the $517.6 million Safeco Field becomes forgettable as closer Jose Mesa squanders a 9th-inning lead by walking four batters, resulting in a 3 – 2 defeat to the Padres. A crowd of 44,607 is on hand.

Source
Baseball Reference July 15