The pair signed one-day contracts and the first question that came up was if Astros manager Bo Porter could use them.
Oswalt and Berkman are two of the greatest players in team history on and off the field and they were honored on the field before the Angels-Astros game.
Both were given gifts including custom rocking chairs.
Berkman was the best switch hitter in team history. Oswalt is second in team wins with 143.
Both remembered the great playoff runs from the mid-2000's.
"For three years, we didn't play a single meaningless ballgame," said Berkman. "From the very first game of the season to the last game of the season, we had neither clinched or been eliminated, three straight years. That's pretty remarkable."
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