* Q4 total sales up 14.3 pct to 317.4 mln stg
* Q4 gross profit up 22.7 pct to 128.6 mln stg
* Says certain of reaching 2013 FY underlying EBITDA target
* To open first store in Poland
LONDON, April 24 (Reuters) - Britain's biggest sporting goods retailer Sports Direct posted a 14.3 percent rise in fourth quarter sales as squeezed consumers found the cash to splash out on sports products.
The group, which owns Sports Direct.com and Lillywhites stores and in February bought failed fashion retailer Republic, said on Wednesday total sales in the nine weeks to the end of March were 317.4 million pounds ($485.16 million), up from 278 million a year earlier.
That followed a 21 percent rise in its third quarter after a strong Christmas.
Gross profit in the nine week period rose 22.7 percent to 128.6 million pounds, the firm said, reiterating that it would meet its 2013 full-year underlying EBITDA target (earnings before interest, tax, depreciation and amortisation) of 270 million pounds, before a charge for bonus share schemes.
While many British retailers have struggled as consumers grapple with rising prices and muted wage growth, heavy discounter Sports Direct has coped well, benefiting from the woes of its rivals, a growing internet presence, staff motivated by a lucrative bonus scheme and expansion.
The firm said online sales now represented 15 percent of its total sports retail sales. On Tuesday plans for the firm's first store in Poland - to be opened in July - were also announced.
Shares in the Sports Direct, which have risen 60 percent in a year, closed at 446.6 pence on Tuesday, valuing the business at around 2.7 billion pounds.