The Lions made a blistering start with six first-half tries as George North impressed with an eye-catching brace but the tourists failed to capitalise on their dominance in the second half.
Warren Gatland made a number of changes and the Lions appeared to lack continuity despite Brian O’Driscoll, Leigh Halfpenny, Sean O’Brien and Jonathan Davies adding further tries.
“We are happy with the first half but a little frustrated by the second-half performance,” Howley, who is Gatland’s assistant coach, told Sky Sports.
“We made a few too many handling errors for our liking, particularly in the opposition 22. It’s frustrating.
“But we’re happy to score two tries and some combinations but with substitutions off the bench, we did lose a bit of continuity.
“We’re generally happy but the second half was frustrating.”
Howley heaped praise on Scotland full-back Stuart Hogg, who deputised for Owen Farrell and Jonathan Sexton at number 10, kicking four conversions in the first half before Halfpenny’s introduction.
“He’s got natural talent. He’s got great feet and he hasn’t got a bad kicking game either,” Howley added.
“I thought he facilitated our centres and backline particularly well. We wanted to play nice and flat.
“He gave opportunities to Brian O’Driscoll and Jamie Roberts at outside backs.
“I’m delighted for Stuart because he can play there.”
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