Beau Mertens has retaken the lead in the Melbourne jockeys' premiership and has a golden opportunity to open up a bigger margin after rival Craig Williams was suspended at Caulfield.

Mertens bagged a winning double on Saturday's program for his boss Mick Kent, taking the apprentice one win clear of Williams.

Williams was suspended for eight meetings for careless riding in the sixth race on Saturday's card, meaning he will miss the next two city meetings unless he successfully appeals.

Only eight city meetings remain.

Williams pleaded guilty to the careless riding charge but told stewards it was "really disappointing" they had decided on an eight-meeting penalty.

He also argued his battle with Mertens was "great for racing".

Williams was charged with shifting in aboard Enigman in the straight in the Securecorp Handicap (1400m), placing Jordan Childs in a position where he had to restrain his mount, Nikitas.

Mertens started the day a win behind Williams but drew level when the Kent-trained Coldstone made ground along the inside in the Sheen Group Plate (1600m) before charging through a gap to win by a half-neck.

The apprentice then was relieved to win aboard Leodoro in the Ladbrokes Handicap (1200m) after admitting he made a mistake on the gelding last start at Moonee Valley, where the horse was held up in the straight and finished an unlucky 10th.

Mertens made sure he had Leodoro ($7) into the clear on the outside this time and the five-year-old charged home from well back to grab Wind Force in the final strides and win by a neck.

Portman was another long neck back in third.

"Obviously I didn't really give him the best of chances last start but for Mick to have the faith to put me back on and trust me with the horse is a big thrill," Mertens said.

"We always knew it was going to be tricky from the wide gate and he had to overcome that. He definitely dug deep and finished off strongly.

"I thought once Craig got past me (in the premiership lead) it would be pretty hard to catch up again but he hasn't got one today and I've got two so it's been a very successful day."