Agnieszka Radwanska was relieved after sealing a 6-4 6-3 win over Britain's Heather Watson in her opening match at this year's BNP Paribas Open in Indian Wells.
On her 25th birthday, second seed Radwanska was broken five times, but she managed to hold serve in the final game to secure victory after 84 minutes.
"The first match is always challenging," Radwanska told reporters. "I'm just happy I got through and finally won my serve in the last game."
Radwanska, who received a first-round bye in the tournament, will face Annika Beck in the last 16.