Easy to back in light of support for stable companion Sir Des Champs, the 4-6 favourite, ridden by Bryan Cooper, was well-positioned from the outset, and jumped with his usual aplomb.
Some eight-to-ten lengths behind pacesetters On His Own and Foxrock for much of the race, he closed up, under pressure, racing around the final bends, and put his nose in front shortly after turning in.
A dour stayer but not known to win his races by too far, there was plenty yet to be done. The early pacemakers were not going away, while the rejuvenated First Lieutenant travelled best of all, in a closing fourth place.
The favourite jumped the last in front, but edged across to the rails and, in doing so, interfered with Foxrock. First Lieutenant, who finished third in the Newbury Hennessy on his previous start, picked up well from the back of the last but, in a pulsating finish and as we have become accustomed to, Don Poli found the necessary to see off all comers.
First Lieutenant ran his heart out to push the winner to half a length, while Foxrock, also back to form, was the same distance away in third place.
On His Own, whose most recent starts were over banks courses, ran a super race to finish fourth, but former Gold Cup runner-up Sir Des Champs failed to fire.
“He never shows off, but just does what he has to - he’s a very lazy horse,” said Mullins, of the winner. “Things were very tough and I think he was probably getting tired after the last, but when the others came at him he kept pulling it out. It’s hard to know how good he is, or how much more he can produce.
“Bryan (Cooper) said he was lazy and thought he was in trouble going to the last, and then he picked up again and went on.
“You have to have confidence in Don Poli. That’s what I have always said to Bryan, and he is getting that confidence in him now. He keeps it for when it matters, and that’s what I like in a chaser.
“I don’t think he’ll run again before Cheltenham. It was even tough coming back here so soon after his first race, but we’ll see what happens. We might have to look at the Irish Gold Cup, but that’s two tough races, one after the other.”
Bookmakers were unimpressed by the display, many choosing to leave his Gold Cup odds unchanged, others lengthened them. Absent stable companion Djakadam had his odds shortened, a move which the pragmatic Mullins could understand.
“That’s the way I would have looked at it, too,” he admitted. “Djakadam’s form is there to be seen. He has been there and was just edged out of it, whereas this was Don Poli’s first time into Grade 1 company since last season. Would the bare form of this race be good enough to win the Gold Cup? I don’t know.
“I know Don Poli is only ever going to win a race, but I don’t think too many people are going to be rushing (to back him).”
Don Poli’s jockey, Bryan Cooper, admitted his relief at getting off the mark at the meeting: “It’s been a tough few days. Thankfully the team is getting winners, but I haven’t been on them.”
Of Don Poli, he added: “I had to race in third place on my own, which isn’t ideal, as he is idle enough without that. But, I was happy enough that I had them covered the whole way.
“I was surprised On His Own picked up the way he did, but I was confident that once I got a good jump at the last that I would outstay them.”
Of his other runners, Willie Mullins added: “I was a bit disappointed with Sir Des Champs, but On His Own ran a cracker. The blinkers worked well and we’ll keep them on in future. I don’t know what direction we’ll go with him, but he’ll get an entry in the Gold Cup.
“In fact, everything will be entered for the Gold Cup. We’re lucky to have the horses we have, and Djakadam will get another run before March, probably at Cheltenham at the end of next month.”