A Cy Twombly chalkboard picture led Sotheby’s contemporary sale on Wednesday evening, setting a record for the artist and beating the $60m presale estimate with a hammer price of $62.8m, or a total of $70.5m including the auction house’s fees.

The New York sale was closely watched as a 10-day auction stretch with record inventory weighed on the market and participants’ nerves.

The sale narrowly beat its presale estimate of $254m by bringing in $256.3m before fees, or $294.9m when the “buyer’s premium” was included. With 81.5 per cent of lots sold, it was one of the stronger sales in the past week, in which few auctions have made it to their estimates amid concern that stretched prices and the summer’s financial market volatility might weigh on the global art market.