In February, Shields inked the largest deal in franchise history at $75 million for four seasons. He's still owed $63 million on that deal.
Shields made $10 million this past season and is set to earn $21 million in each of the next three seasons. There's a club option for 2019 for $16 million, with a $2 million buyout.
It's worth noting that Shields also has an opt-out clause after '16, should he choose it.
Shields, who will turn 34 on Dec. 20, was 13-7 with a 3.91 ERA in 33 starts in his first season with the Padres, surpassing the 200-inning plateau for the ninth consecutive season.