The Australian ended Thursday's track running fifth overall, 1.4s down on Ferrari pacesetter Carlos Sainz after both had used the C4 soft tyre.
It followed Ricciardo setting the fourth-fastest time on Wednesday, 1.2s off pacesetter Max Verstappen in the Red Bull RB20, but on a par with the McLaren of Lando Norris and Sainz.
The team formerly called AlphaTauri has undergone a revamp over the winter, with Laurent Mekies coming in as team principal and Enstone veteran Alan Permane joining as racing director.
Despite the promising start, Ricciardo has urged not to read too much into the times.
Speaking on Wednesday, he said: “Start of the season, we need to be a little bit cautious.
“The target as the season goes on is the front of the midfield. But I would say now where we are, it's probably more in the midfield.
“I'm not sure yet at the front. But that is certainly our target. I know some people are quite excited about us coming into the season, but I want to play it a little bit cautious.
“We have a decent car, but we still have a lot of work to do, and the numbers we brought for the test, we believe there's still some things to find.”
Source: Autosport