Marc Jacobs, known in recent years to favor leather kilts as formalwear, has seemingly turned his back on the style in favor of a comfier ensemble: pajamas. The undisputed king of modern American sportswear (he’s probably the only designer in New York who could get away with postponing his show four days and still receive rave reviews) appeared in PJ’s at both of his New York Fashion Week shows.

At Monday evening’s Marc by Marc Jacobs presentation at Lincoln Center, Jacobs took his final bow in a pajama-y black watch plaid shirt and matching pants, worn with white sneakers. On Thursday he took his final send-off in a patterned eggplant silk ensemble. Both were intelligent choices for their respective occasions: flannels for Jacobs’s less expensive, younger line, and silk for his luxury label Marc Jacobs Collection.

Both outfits were indicative of Jacobs’s mood for the season. While pajama-inspired day clothes have been standby trendy items for retailers like Club Monaco and J.Crew in the last two years (a trend that was actually initiated by Jacobs’s 2012 resort collection for Louis Vuitton), the designer’s sumptuous take on the trend made it look new again. He constructed round-collar shirts in silhouettes signature to Brooks Brothers’s chambray PJ’s out of a stiff duchesse satin--giving them a structured, blazer-like appeal.