Leclerc finished fifth on the road and one place ahead of Alonso but dropped to sixth after receiving a five-second time penalty for speeding in the pit lane.
The Monegasque pitted when Ferrari made a failed bid to snatch the fastest lap point away from race-winner Max Verstappen by calling Leclerc in for soft tyres on the penultimate lap.
Leclerc was overtaken by Alonso along the Kemmel Straight before repaying the favour on the final lap. However, Leclerc’s time penalty resulted in him slipping back behind Alonso to sixth.
Asked if he was surprised to see Leclerc pit so late, Alonso told Sky: “Yeah I was surprised.
“But Ferrari always does some strange strategy, so that was one of those.”
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