Wales manager Chris Coleman admits their Euro 2016 opponents will target them at set pieces after they were exposed again in Ukraine.
Coleman's side slipped to a 1-0 defeat in Kiev on Monday night when Andrij Yarmolenko finished expertly from Ruslan Rotan's 28th-minute free kick.
That set-piece frailty is a familiar theme for Wales as just four days ago Craig Cathcart punished them from a corner in a 1-1 draw with Northern Ireland.
Wales also conceded twice from set plays in a 2-0 Euro 2016 qualifying defeat to Bosnia-Herzegovina last October, and Coleman accepts opponents will target them in this area in France this summer.
"In both games [against Northern Ireland and Ukraine] I was pleased overall with the players," said Coleman.
"The only thing I'm disappointed with is that we conceded both goals from set plays and sometimes a pattern can emerge.
"First of all, I must look at myself as a manager and a coach and look to adjust something in the preparation.
"I will look at that because if you look at our record in open play in the last 15 games the amount of goals we've conceded is not very much.
"I'm not giving any secrets away, the opposition will look at the stats [of Wales conceding from set-plays].
"It's definitely something we need to go and work on."
Coleman had said before the game that heading to Kiev was a "risk" given the sort of test posed by fellow Euro 2016 finalists Ukraine and the environment Wales were heading into.
Wales were also without their two most influential players, Gareth Bale and Aaron Ramsey, once more, but Ukraine took time to settle and Yarmolenko scored from their first meaningful attack.
After the interval, Ukraine were happy to play on the counter-attack and Joe Allen, Jazz Richards and Shaun MacDonald all forced saves from Andrij Pyatov in the home goal.
"It's never easy to come here, even at full-strength it would be a tough game," said Coleman.
"We've come to a tough place to play but we were the team that dictated.
"Apart from the goal, Wayne Hennessey has had one shot to save and we were always the team dictating the tempo of the game.
"We know it's a good test for us because when we play Russia and Slovakia in the Euros it will be very similar."
Ukraine coach Mykhaylo Fomenko declared himself delighted with the end result, even if he admitted there was room for improvement ahead of a Euro 2016 campaign which will see them come up against Germany, Northern Ireland and Poland.
"This was just a friendly game. We did something right, something wrong -- but I can be satisfied with the result," said Fomenko.
"Wales, like Northern Ireland, are difficult because it is British football, but they are different teams.
"But we showed we can be different in our tactics and we have shown what we need to do.
"It is two months before the Championships and we will be prepared for the tournament."