Substitute Chioma Ubogagu scored on her Women's Super League debut to rescue a point for Arsenal at Notts County.
Ellen White opened the scoring for the hosts with a theatrically-worked training ground free-kick.
White missed the chance to add a second from the penalty spot after being brought down by Jemma Rose less than two minutes later.
Arsenal, who rarely threatened, made the hosts pay for their profligacy when Ubogagu levelled with a half-volley.
The draw for Pedro Martinez Losa's Gunners came 11 days after their only other match this season, a 7-0 FA Cup fifth-round win over Millwall.
Forward White's first Women's Super League goal for Notts County came more than 15 months after the England international moved to Meadow Lane from the Gunners, having missed the entire 2014 season with a knee injury.
Following some play-fighting from Laura Bassett, who appeared to begin to argue with Alex Greenwood as she approached to take the free-kick, the ball was worked out for White to send a curling effort into the bottom corner from 18 yards.
Notts County manager Rick Passmoor:
"Score the penalty and go two up and it's a completely different game. Credit to Arsenal, they managed the game in the second half to create, not the chances but to retain the ball a lot more than they did in the first half and so they gradually improved.
"We were badly positioned for their goal but it was a good goal. A point against Arsenal, I've got to be happy with that as they will be up there come the end of the season in the WSL.
"I'm perhaps a bit disappointed not have the three points because I think our attitude and work-rate and our first-half performance could have given us that."
Arsenal manager Pedro Martinez Losa:
"I think there was nothing else we could do, the first 5-10 minutes we were doing really well, but after Notts County were playing their own game, they were doing fantastic.
"In the second half it was more equal, so scoring towards the end we have to say with the opponent missing the penalty, we are never happy as Arsenal having a draw but we'll take a point.
"I said to the girls at half-time we were still alive, it was a bad first half but this is football and it always gives you a chance. We were trying to give the team motivation and told them to be more aggressive and more physical and winning more second balls, which had been difficult for us and also we changed a little the formation and it certainly helped.
"We've wanted to get the season started and play last week, because we know where we are and can improve and analyse what areas the team are doing well."
Notts County: Telford; Greenwood, Buet, Bassett, Turner; Whelan (Susi 72), Walton, Crichton, Clarke; Williams, White.
Subs Not Used: Jules Draycott, Fiona O'Sullivan, Fern Whelan, Jessica Sigsworth, Laura-Jayne O'Neill
Bookings: White (77)
Arsenal: Byrne; Mitchell, Rose, Stoney, Scott; Losada, Nobbs, Weir; Carter, De Pablos Sanchon, Sanderson (Ubogagu 64)
Subs Not Used: Smith, Chamberlain, Clarke, Hassall, Bailey, Oliver
Bookings: Nobbs(63), Stoney (79)
Referee: Stephen Ross