Leah Williamson says Arsenal were "a team on a mission" following their impressive turnaround in their Champions League semi-final first leg against Lyon.

The Gunners came from behind at the Emirates Stadium, where they trailed to Jule Brand's first-half strike, with an Ingrid Engen own-goal levelling, before Olivia Smith scored a late winner.

Arsenal claimed their first-ever victory in a Champions League semi-final first leg, while condemning Lyon to their maiden such defeat.

The eight-time champions also suffered their first-ever loss on English soil, and Williamson, who returned from injury in the heart of defence, saluted her team-mates' efforts.

"The first half was quite even," she said. "We gave away a cheap goal, but what you saw in the second half was a team on a mission, fuelled by the crowd.

"For us to give the fans a win and pay them back for their support is the nicest thing. It's a nice moment to celebrate."

When the sides met at the same stage of last season's competition, Arsenal travelled to the Groupama Stadium for the second leg with a 2-1 deficit, before recovering to progress to the final.

Williamson believes things will not be too dissimilar this time around, with the reigning champions aiming to become the first English club to reach successive finals.

"Last year, we had a tough task, and it rallied us together," she added. "I don't think the mentality will be too different.

"Intensity will be key. Lyon are giants of European football, they have a great crowd, like we do, so an intensity that matches that occasion, and we have to be really clinical, defensively secure, and we'll see."

Arsenal boss Renee Slegers also knows her side will be in for a tough return fixture next weekend, but was thrilled with her players' first-leg exploits.

"It's only half-time [in the tie], but if you look at the game, a lot of bits played out how we wanted it," she said.

"There was a phase in the first half where we wanted more aggression in our press, and I think we had some great solutions at half-time.

"We have a brilliant goalkeeper and a fantastic backline. We kept them away from our box, and they had one shot on target and one corner was conceded.

"We have a lead now after 90 minutes at the Emirates. It will be very challenging, and we will have to be really good in that second leg. We respect them, but we also respect ourselves."

Lyon have reached more Champions League semi-finals (15, including this season) and finals (11) than any other team, though they now face an uphill battle to avoid consecutive last-four exits for the first time since 2007-08 and 2008-09.

"As expected, it was a very difficult game," Brand told UEFA. 

"Arsenal played really well and put pressure on us. I don't think we were able to show our full quality on the pitch, but I am still confident in the team that we can [win the semi-final]."