Top-seed GM Yu Yangyi of China scored an emphatic win in Friday night’s seventh round to grab a share of the lead with defending champion GM Aravindh Chithambaram of India, who continued to struggle pulling the trigger in another promising position.

Yu and Chithambaram now have 5.5 points from seven games, half a point ahead of a chasing pack of eight players entering Saturday’s penultimate eighth round of the 23rd Dubai Open Chess Tournament at the Dubai Chess and Culture Club.

Yu defeated Armenia’s GM Shant Sargsyan, who was unable to get any advantage with the white pieces in a Slav Opening, conceding the full point after 58 moves in a game dominated by the Chinese top-seed from start to finish.

Sargsyan’s opening play hinged on an idea of breaking through the center with the pawn push to e4, but the Armenian had delayed the move far too long that by the time he had played it, Yu was already in total control of the proceedings.

However, by move 44 the Armenian did get a chance to force an endgame with roughly equal chances for both sides by piling his rook on the d-file; instead Sargsyan played an errant knight move that allowed Yu to liquidate the position into a winning rook-and-knight vs rook-and-bishop endgame with pawns on both wings, which the Chinese did not have problems converting.

For the third straight game, Chithambaram played exceptionally well for the majority of the game, only to falter once again in the endgame to let Russia’s GM Maxim Matlakov slip away with a draw.

Chithambaram went for the Closed variation against Matlakov’s Sicilian defense, opting for a quieter treatment that paid great dividends as the Indian gradually worked his way towards a winning position by move 20.

Although he had built a powerful queen-rook battery on the h-file in a dangerous attack against the black king, Chithambaram could not find anything better than convert into a rook endgame that was still much better for white.

Chithambaram’s 32nd move, which was played after a long think of more than seven minutes, leaving the Indian with just a little over one minute on his clock, gave away all his advantage as Matlakov’s passed g-pawn proved more than enough for equality. The two players decided to split the point 10 moves later.

In Saturday’s eighth round, Yu will have the white pieces on the first board opposite GM Arjun Erigaisi of India, while Chithambaram will play fellow former Dubai Open champion GM Abhijeet Gupta of India on board two.

Erigaisi, who drew with GM Amin Tabatabaei of Iran, and Gupta, the 2011 champion who defeated GM Vugar Asadli of Azerbaijan, are at joint second place with five points each. Others with five points are Tabatabaei, GM Javokhir Sindarov of Uzbekistan, GM Volodar Murzin and GM Maksim Chigaev of Russia, and GM Ilia Smirin of Israel.

Bryle Arellano of the Philippines scored a big win over erstwhile co-leader Ediz Kocak of Germany to take a share of the lead with FM Maxim Gavrilov of Russia, who drew his game with Kevin George Micheal of Egypt in the Open division.

Kocak had a monumental mental lapse when he tried to force the issue in an otherwise equal game, walking into a relatively easy tactical shot as he tried to get away from a perpetual check by Arellano.

Gavrilov and Arellano have six points each and will contest the solo leadership in Friday’s eighth round.

Five players share second place with 5.5 points: Kocak, George Micheal, second-seed WFM Alexandra Zherebtsova of Russia, Jaiveer Mahendru of India and Manvel Arakelyan of Aremania.

The final round of the tournament will be played at 10am on Sunday, followed by the awarding ceremony at 7pm at the Dubai Chess and Culture Club.

A total prize fund of $52,000 will be awarded to the top 10 players of both categories.

The Masters category champion will receive $12,000 and the championship trophy, while the Open category champion will receive $2,000. Special prizes will also be awarded to two rating category winners for both the Masters and Open events.