Logano has one win and two podiums in five starts this season, and sits second to Busch in the Cup standings.
Busch dominated the majority of Sunday's Fontana race at Auto Club Speedway, leading 134 of the 200 laps to take his 200th win across NASCAR's three main series, but his attempt to win was almost derailed by a pitlane speeding penalty.
But a free pitstop under a caution - while others had stopped under the green flag - brought Busch back into the lead battle, and he eased ahead with 26 laps remaining to take a commanding win.
Despite leading in the closing stages, Logano said his and the team's performance was lacking relative to Busch.
"We only raced for two laps before [Busch] blew our doors off and drove away from us," said Logano.
"Fastest car in the race [was Busch].
"We've got a little bit of work to do.
"We came so close. I'm proud of the effort. Hung in there all day, hung strong. Just didn't have enough for the green car [Busch]."
Logano's team-mate Brad Keselowski - who has also had a strong start to the year and is fifth in the standings - said the wind had contributed to his inability to hold off Busch in the closing stages. He finished third.
"We were so strong in practice," said Keselowski, who won the second round of the season at Atlanta.
"The track changing kind of threw us for a loop with the wind. [I] just never could get right off of Turn 2.
"It ended up kind of costing us the race there. I couldn't stay in front."
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