Seeds Karin Knapp and Ajla Tomljanovic fell at the first hurdle in the inaugural Aegon Open Nottingham, but Alison Riske safely negotiated her way into round two on Monday.
The grass-court tournament, which has a winner's trophy named in honour Elena Baltacha who died as a result of liver cancer in 2014, began with a couple of surprises.
Italian Knapp was the first to fall. The fourth seed was below her best in a 6-4 6-2 defeat to Yanina Wickmayer in a match lasting little over 80 minutes.
Wickmayer may be ranked 51 places below Knapp, but she broke serve on four occasions in an impressive outing.
Tomljanovic, seeded eighth, appeared on course for round two before American Lauren Davis produced a fine comeback to win 4-6 7-6 (7-1) 7-5.
Davis was staring down the barrel when Tomjlanovic broke in the ninth game of the third set to take a 5-4 lead, but she rebounded to reel off three straight games to clinch the win.
Fifth seed Riske saw her contest with Zheng Saisai suspended due to rain when leading 3-0 in the second set. The break halted her momentum slightly as the Chinese broke serve when the match resumed, but Riske ran out a comfortable 6-3 6-4 winner.
Elsewhere, Mirjana Lucic-Baroni and Bojana Jovanovski overcame second-set blips to defeat Stefanie Vogele and Nicole Gibbs in three sets, while Ana Konjuh easily accounted for Shelby Rogers 6-0 6-3.
Magdalena Rybarikova, seeded seventh, and home favourite Johanna Konta were scheduled to play last on Monday, but the delay earlier in the day saw their match put back to Tuesday.