Kent captain Robert Key and Martin van Jaarsveld led their county to safety with unbeaten centuries to put a dent in Derbyshire's promotion hopes.

Key batted through the final day to score 141, his fourth LV County Championship hundred of the season, and Van Jaarsveld (101 not out) completed his sixth to secure a draw that took Kent a step closer to a return to Division One.

Geraint Jones also made a half century, while Key and Van Jaarsveld shared an unbroken stand of 194 to frustrate the home side who took only one wicket before the teams shook hands with Kent 31 runs ahead on 333 for two.

Kent went into the last day trailing by 258 runs with a lot of batting to do, but the pitch had flattened out and Derbyshire never looked like taking nine wickets.

They had to wait until three overs before lunch for their only success which came when Greg Smith surprised Jones with some extra bounce.

But apart from Key surviving a sharp catch to slip, there were few other alarms for the Division Two leaders who are now 27 points clear of third-placed Gloucestershire with a game in hand.

Derbyshire needed to strike early to put Kent under pressure but Key and Jones gave them little encouragement as they took their second-wicket stand to 133 in 39 overs.

Jones followed his first-innings hundred with another fifty which he reached by lifting Graham Wagg's left-arm spin over the long-on boundary.

The former England wicketkeeper was eventually snared at short leg off Smith's off spin for 60 and at lunch, a Derbyshire victory was still a possibility with Kent 156 runs behind on 146 for two.

The visitors might have had an uncomfortable afternoon if Chris Rogers had clung onto a low catch offered by Key on 77 when he edged Smith but after that, the game drifted towards an inevitable draw.

Key escaped with a couple of top edged pulls over the wicketkeeper's head before he raised his bat to acknowledge his second century in a month against Derbyshire.

Van Jaarsveld pulled Wagg for six on his way to a hundred that he reached off the bowling of wicketkeeper Jamie Pipe as the game ended on a note of farce.

He was the eighth bowler Derbyshire had used in the day and the fact that only 16 wickets fell and six century partnerships were shared in the game highlighted how easy the pitch had become.

Derbyshire's 10th draw of the season takes them into fourth place above Essex, who still have to come to Derby, with two games to play.