A classy unbeaten hundred from Moeen Ali handed Worcestershire the momentum on the opening day of their LV= County Championship Division Two encounter against Surrey at the Kia Oval.
The England man was unbeaten on 138 at the close of play as Worcestershire reached 329 for four at stumps.
Worcestershire won the toss and chose to bat first - a decision that was vindicated by Moeen, Matthew Pardoe and captain Daryl Mitchell's heroics with the bat.
Amid gloriously warm conditions in London, Worcestershire made steady progress against the hosts’ seam trio of Matt Dunn, Chris Tremlett and Jade Dernbach, reaching 40 without loss by the end of the 10th over.
Pardoe was especially finding the conditions to his liking as he regularly dispatched Surrey's bowlers to the boundary and he brought up his half-century with a four off spinner Gareth Batty, the final delivery of the 19th over.
Batty got his revenge in the next set of six when he bowled Pardoe to give Surrey a long-overdue breakthrough. Pardoe's 62-ball innings of 52 included eight fours and helped Worcestershire to 88 for one.
Number three Moeen picked up where Pardoe left off, with the left-hander clubbing Batty to the ropes from the first ball he faced.
Moeen then proceeded to launch Batty for a four and a six in the 23rd over as the Worcestershire scoreboard kept ticking over - Mitchell happy to play the support role as he had with Pardoe.
With Mitchell and Moeen in good nick, Worcestershire reached lunch on 129 for one as Pardoe's wicket was the only one to fall in the first session.
Mitchell brought up his half-century at the end of the 39th over with his first boundary for 24 overs. The milestone took 92 balls and contained six fours.
Nine overs later and Tremlett brought Mitchell's innings to a close on 62 - the 30-year-old bowled with his side in good shape on 175 for two.
Moeen dispatched Dernbach to the boundary to bring up his fifty at the start of the 54th over and with Tom Fell for company, Worcestershire moved to 232 without further loss at tea with Moeen on 75 and Fell 25.
A leg-side single off Zafar Ansari saw Moeen enter the 90s in the 70th over and he raised his bat after reaching triple figures five set of sixes later.
A quintet of overs after and at last Surrey had something to smile about when Ansari pinned Fell lbw for 41 to bring number five Alexei Kervezee into the action.
Kervezee's stay at the crease was short as he edged a Tremlett delivery to second slip where Jason Roy held on to secure Surrey's fourth dismissal of the day in the 82nd over.
Worcestershire were to reach the close without further loss, with Moeen on 138 and Ross Whiteley for company.