The stars announced their split earlier this month
The Mad Men actor, who’s nominated for outstanding lead actor in a drama series, skipped the carpet – where temperatures soared into the high 90s – and went straight into the Microsoft Theater for the show.
Hamm and Westfeldt, 45, announced their breakup in a joint statement Sept. 7 after being plagued with split rumors for months.
“With great sadness, we have decided to separate, after 18 years of love and shared history,” the couple told PEOPLE. “We will continue to be supportive of each other in every way possible moving forward.”
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