After six years away and with acknowledged difficulties resulting from the injuries to his right arm, Robert Kubica's return to the cockpit of a current F1 car at the Hungaroring test was by far the most anticipated thing of the 2017 season so far.
The Polish driver did not disappoint, setting fourth fastest time of the day and running several race distances to prove both speed and endurance are there, ready for a full return to the cockpit.
Of course being an F1 driver and enormously competitive (that was never in doubt) Kubica said that he wasn't completely happy with the results of the test. But to end the test as Renault's fastest driver and to post a headline lap time and long run times which were comparable to those set by the team's race drivers at the weekend's Grand Prix put down a serious marker.
Renault has a tough decision to make. Kubica's return has thus far produced more positive reporting about the team than half a season of racing by Hulkenberg and Palmer. The latter has managed to combine bad luck with mistakes to disappoint so far. On the basis of Kubica's single day of running you'd have to say a swap sooner rather than later would benefit both the team and Kubica.
Palmer is already rumoured to have turned down a pay off from the Renault team - which suggests a remarkable return for Kubica is very much on the cards.
I imagine the Renault team management have some serious thinking to do over the summer break.