BALTIMORE -- Chad Smith's first major league win came courtesy of a rarely applied official scoring rule.

It was an unusual twist at the end of a long day for the Oakland reliever.

Smith pitched the final two innings of the Athletics' 8-4 victory over Baltimore on Wednesday night, holding the Orioles scoreless and allowing only one hit. He entered in the bottom of the eighth, after the A's had scored three runs in the top of the inning to take a 7-4 advantage.

That meant reliever Jeurys Familia -- who pitched the bottom of the seventh and was in the game when Oakland took the lead for good -- could have been the pitcher of record. But the official scorer chose not to give Familia the win because he was deemed to have had a short, ineffective outing.

Familia came on with one out in the seventh, a man on first and Oakland up 4-2. After a passed ball, pinch-hitter Cedric Mullins rolled an RBI single to right, and after a groundout moved Mullins to second, Adley Rutschman hit an RBI single to tie the score.

Familia retired Ryan Mountcastle on a grounder to end the inning.

According to Rule 9.17 (c): "The official scorer shall not credit as the winning pitcher a relief pitcher who is ineffective in a brief appearance, when at least one succeeding relief pitcher pitches effectively in helping his team maintain its lead. In such a case, the official scorer shall credit as the winning pitcher the succeeding relief pitcher who was most effective, in the judgment of the official scorer."

The rulebook also says: "The official scorer generally should, but is not required to, consider the appearance of a relief pitcher to be ineffective and brief if such relief pitcher pitches less than one inning and allows two or more earned runs to score (even if such runs are charged to a previous pitcher)."

One of the runs in the seventh was charged to Familia and one to starter Ken Waldichuk.

Smith was called up from Triple-A Las Vegas and had to wake up early in the morning to fly to the game. He struck out three without a walk.

"Woke up this morning at 2:45," Smith said. "On the plane and then got here. The adrenaline kicked in today and helped me get through all that."

He didn't seem to realize he'd gotten the win until he spoke with reporters afterward.

"I was told it was a save," he said -- and it would have been if he hadn't been credited with the win.

"I guess now that you say it's a win, I guess it's a win," Smith said. "It's great. This is why we play the game."

This was the 16th big league appearance for the 27-year-old Smith, who made his debut last year with the Colorado Rockies.