Swansea's Slovenian striker Zan Vipotnik has scored seven goals in nine games for club and country
Swansea City and Millwall maintained their respective unbeaten home and away records as they fought out a 1-1 draw in the Championship.
The Swans controlled much of the first half and took an early lead as Zan Vipotnik instinctively diverted a shot from Ronald with a clever backheel - the Slovenian's sixth goal in seven games.
But they were made to rue their inability to add to that lead as Millwall equalised on the cusp of half-time through Josh Coburn's close-range header.
A less eventful second half sparked into life with a flurry of chances at either end, with Millwall substitute Macaulay Langstaff seeing a goalbound effort blocked by Ben Cabango.
Vipotnik then appealed in vain for a penalty after claiming to have been pulled back as he looked to latch on to a cross.
Millwall remain unbeaten on the road this season and move up to eighth in the Championship table before Saturday's 15:00 BST kick-offs.
Swansea, meanwhile, remain 11th and have now gone 11 games in all competitions since tasting defeat at home.
Analysis: Millwall recover after Sheehan's style comes to fore
Swans head coach Alan Sheehan had given some interesting insights into his coaching style in the build-up to this game, explaining how he would ideally want his team to play.
Unlike some of his predecessors, who set out to pass opponents into submission, the Irishman said his philosophy is more focused on getting forward quickly, winning possession and then trying to hurt teams in the transition rather than, as he put it, "just having the ball".
Swansea's opening goal was a clear illustration of that approach, as Zeidane Inoussa regained possession near the Millwall penalty area, drove forward and crossed for Ronald, whose low shot was backheeled into the net by Vipotnik.
The Swans had opportunities to extend their lead, with Inoussa firing agonisingly wide after Ethan Galbraith went close with a curling effort from 25 yards.
However, they gradually allowed Millwall back into the contest, and the visitors were denied what seemed a certain leveller when Coburn was denied on the line by a sliding Cabango.
That was not much of a reprieve as, four minutes later, the visitors launched a deep free-kick towards the back post, where Jake Cooper headed the ball across goal for Coburn to nod in.
The second half was a scrappier encounter but, in the closing quarter of an hour, both sides had chances to win.
A defensive calamity from the home side presented Langstaff with a golden opportunity, but his shot was well blocked by Cabango.
Ronald fired over wastefully for Swansea, who then thought they should have had a penalty when Vipotnik went down under pressure from Cooper.
The hosts also had the ball in the net late on but substitute Adam Idah had kicked the ball out of the hands of Millwall's former Swans goalkeeper Steven Benda.
The Republic of Ireland striker appealed for that goal more out of hope than expectation and, in truth, a draw was a fair result for two sides who were far from their best on this occasion.
Post-match reaction
Swansea head coach Alan Sheehan:
"In the first half we were very good for large amounts. I think we got the goal when we were on top and then we continued to try and get the second one, and then right on a stroke of half-time we concede the set-piece.
"These are the things you've got to do properly against Millwall. You know the percentage of goals, what we've got to negate, to come out on top. We didn't defend that properly.
"In the second half there were a lot of stoppages, but I think we had control of possession, created some opportunities. It's really fine margins. We've got to find a way of getting that second goal."
Millwall head coach Alex Neil:
"I thought it was a really hard-fought game. I thought Swansea were better for 20 minutes. They started brightly, first to every ball.
"I thought we grew into the half. We looked threatening. The boy Cabango does unbelievably well to get his foot in front of Josh and put it over the bar from about two yards. It's a great chance for us.
"Swansea were aggressive and we didn't match that for the first little bit of the game, which is disappointing. But as the game wore on, I thought we got better. I'm pleased with a point."
Alex Neil post Swansea City
