 In the build @-@ up to the Japanese Grand Prix , Alonso noted that although addressing the power unit 's shortcomings remained the team 's biggest challenge , he was unhappy with some of their trackside operations , citing a lack of running in Friday practice sessions , under @-@ preparedness in starting procedures and pit stops , and unreliability of other parts — such as the gearbox — as compounding the problems with the engine . After being powerless to defend against repeated overtakes during the race , Alonso was overheard condemning the RA615H as " embarrassing " and a " GP2 engine " over the radio . 
