All four Ducatis lagged behind Honda and Yamaha at the opening test, prompting Dovizioso and Nicky Hayden to call for major changes.
On a rain-hit opening to the second test however Dovizioso said he could already feel the impact of improvements. He finished just over 1.2 seconds down on pacesetter Dani Pedrosa.
"I'm pretty satisfied with today. My feeling with the bike has improved, and now I know it better than I did two weeks ago here at Sepang," Dovizioso said.
"We tried something with the fuel tank and also the weight distribution, [and] the bike improved.
"This is important: to feel something different in a good way, to improve the feeling.
"The lap time is not too bad for the first time; not fast like everybody else but the gap is smaller than the last test.
"I used just one set of tyres, so all things considered, the gap to the top is acceptable."
Nicky Hayden, who finished three tenths of a second down the road from Dovizioso, was also convinced that Ducati had made progress.
"Ducati brought a couple of things to try, mainly some changes to weight distribution, which helped make the bike a little nimbler on change of direction," he added.
"Also, I'm able to brake better with the same amount of pressure on the lever.
"We know the gap to the front is still too big, but we're slowly making progress, and hopefully we can reduce it further over the next two days."