Ronnie O’Sullivan is in command despite not hitting the heights (Picture: Getty Images)

Ronnie O’Sullivan leads Ryan Day 10-6 after the second session of their World Snooker Championship last 16 contest, despite struggling to find his best form over Sunday evening.

The morning session on Sunday saw the Rocket take a 5-3 lead and while that is a perfectly acceptable start, he did give up more chances than you might expect to his opponent.

That pattern continued in the evening, with both men missing plenty of balls and frustrations mounting.

Dynamite really did have a lot of chances to capitalise on a mis-firing Rocket, but continued to breakdown and let the world number one back in.

Such is the immense quality of the seven-time world champion that even while struggling for fluency he made breaks of 82, 65, 89, 56 and 96 over the eight frames.

Day finally managed to string breaks together to stay in touch at the climax, winning the final two frames with efforts of 72 and 75 to stay alive at 10-6 behind.

O’Sullivan showed his frustration in the last as he missed a pretty straightforward red and then swung his cue in anger.

Ryan Day will be pleased to be in contention but frustrated with missed chances (Picture: Getty Images)

Not too often will O’Sullivan’s pot success be at 90 per cent, but that’s how he finished the second session, with his long pot success down at 44 per cent.

However, he remains in a commanding position, thanks to Day’s pot success being down at 87 per cent, which won’t cut it against the Rocket.

The pair will play to a finish on Monday afternoon from 1pm in their race to 13, which O’Sullivan remains a hot favourite to win.

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