Given the recency of the trade and how long he played for the D-backs, Kennedy said there was an unusual atmosphere for the game.
"It was only what, three weeks ago, maybe a little over that I had been traded," Kennedy told Arizona Sports 620's Dan Bickley with Vince Marotta on Wednesday. "I described it like a more intense spring training game or intrasquad-type thing. It was so fresh since I was just teammates with those guys."
Kennedy said it didn't really kick in until Paul Goldschmidt came to hit.
"I have friends on other teams but it's different when you play with them for so long," Kennedy said. "You would play with a guy, like I became pretty good friends with Lyle Overbay and I pitched against him, but it's not like the whole lineup. It's one guy."
Padres manager Bud Black was very helpful according to Kennedy, as he pulled the pitcher aside before the game and tried to walk him through what it was going to be like.
Kennedy said his skipper told him it was going to be different, and that while there were going to be some smiles, the best thing to do is just make the "weirdness" go away a little quicker.
Kennedy added he's happy to be in San Diego, saying, "If you're going to live anywhere I guess, you're going to live in San Diego." He's also appreciated having a different set of coaches and players work with him to help improve his performance on the mound.
The D-backs play at San Diego September 23-26, so there's a strong chance Kennedy could face his former club again this season.