Scotland's second-half performance "was nowhere near where it needed to be" after they "got complacent" in their narrow Six Nations victory over Wales, says captain Finn Russell.
The Scots looked nailed on to secure a first win in Cardiff since 2002 when Duhan van der Merwe's superb try put them 27-0 up early in the second half.
However, they conceded 26 unanswered points as Wales almost pulled off one of the great Six Nations comebacks.
Gregor Townsend's side were able to halt the Welsh momentum and squandered a chance to score a bonus-point try of their own at the death, but Russell believes Scotland have to improve for the rest of the championship.
"We're a little bit disappointed, to be honest," the Bath fly-half said. "The win is brilliant but that second half was nowhere near where it needed to be. Our discipline was poor and two yellow cards allowed Wales back into it.
"When we scored that try at the start of the second half we probably got a bit complacent and thought the game was done.
"The pleasing thing was that at the end of the game we managed to hold them out. There are a lot of positives but we need to be a lot better."
Head coach Gregor Townsend was keen to stress the importance of ending Scotland's 22-year Cardiff hoodoo, but agreed with his captain's assessment of the second-half display.
'Shocking' discipline almost costs Scotland dear
In the first half, Scotland were in cruise control.
Russell and Ben White's kicking game controlled proceedings, and they kept the scoreboard ticking over at regular intervals, as Russell's boot and tries from Pierre Schoeman and Van der Merwe gave them a 20-point half-time lead.
After Van der Merwe's second try, a rout looked on the cards. Instead James Botham powered over for Wales, George Turner was sin-binned and calm was replaced by sheer panic.
The rush defence that strangled Wales in the first half was replaced by a backpedalling line as Scotland conceded 14 consecutive penalties and the home crowd stirred.
Sione Tuipulotu followed Turner to the bin as Scotland handed Wales the initiative.
"The penalty count went against us - that pressure will tell," Townsend said. "There's more to it than that, but that put the pressure on us, and then we didn't make the best decisions.
"It's a funny one. A lot of our players are disappointed and we're trying to say to them this is an important win for the next few weeks of the championship, but also in terms of not winning here for so long.
"We were disappointed with the game getting so close and it could have gone either way with the momentum Wales had in the second half."
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