This is the second successive year Radwanska has fallen at the first hurdle in Eastbourne - and the ninth time in the past 15 years the top seed has lost their opening match - although she will take comfort from the fact that last year's setback preceded a runner-up finish at the All-England Club.
"I think playing her in the first match on the grass was tough, and the fact that she played three matches before helped her a little bit," Radwanska said. "Of course, I was practicing here a couple of days, but I think matches are a little bit different than practice. I think I wasn't maybe quite match ready yet.
"Now I can just hope things turn out like last year! I lost first round here but still ended up playing great tennis at Wimbledon."
There were no such difficulties for fellow seeds Li Na, Angelique Kerber and Petra Kvitova, all of whom posted straight set victories. Like Radwanska, Kvitova lost in the first round 12 months ago, but avoided a similar fate this time, defeating Monica Niculescu, 64 61, while Kerber edged out Sorana Cirstea, 64 64, and Li Na won 62 64 against Alizé Cornet.
Wozniacki, who was leading 62 22 at the time, will face Laura Robson in the next round in a rematch of their recent French Open encounter. On that occasion, Wozniacki won in straight sets, but is expecting a sterner test on the Devonshire Park lawns.
"Obviously it's going to be a different match," Wozniacki said. "I'm sure she likes the grass better than the clay so it's going to be tough.
"She can serve very well, and she's going for it from the first ball. So she definitely offers a real challenge on the fast surfaces."
Robson looked impressive in her first round assignment against qualifier Yuliya Beygelzimer, firing down eight aces en route to a 63 62 win.
This year has been an up and down one for Robson, with notable victories over Radwanska, Kvitova and Venus Williams, punctuated by eight opening round exits, including last week in Birmingham.
"I've worked a lot on my game in the last couple of weeks, and it was definitely better than in Birmingham," Robson said. "It's something that's just going to take time, and I need more matches like this to feel confident.
"Overall, I'm pretty pleased. I thought I served very well, which always helps, and that's something I have been working on a lot. I'm happy with that, but I'm definitely going to have to step it up another level against Caroline."