Santa Cruz agreed to a four-year deal with Blackburn on 28 July 2007.
The club agreed to pay Bayern Munich £3.5 million for the player, where he was presented with the number nine shirt.
The striker made his debut in the 2007–08 Premier League on the opening day of the season in a 2–1 away win against Middlesbrough on 11 August, where he was substituted onto the field for the injured Benni McCarthy in the 60th minute and after just three touches of the ball scored an equaliser in the 63rd minute.
Two weeks later, he scored for Blackburn after 16 minutes in a 1–1 draw against Everton on 25 August.
He celebrated his 26th birthday and his first full Rovers start when he scored in a 1–0 away first-leg win against MYPA in the 2007–08 UEFA Cup qualifying rounds on 16 August.
He scored his first hat-trick for Blackburn in a 5–3 loss to Wigan Athletic on 15 December, Blackburn had been losing 3–0 before he had brought the sides level with his three goals.
This hat-trick meant that he became the first player in over ten years in English football to score a hat-trick for the losing side, since Dwight Yorke's hat-trick on 30 September 1996 for Aston Villa in their 4–3 away loss to Newcastle United.

During the 2007–08 League Cup, he scored a brace in a 3–2 loss against Arsenal.
Two weeks later, he scored a brace in a 2–2 draw against Manchester City on 27 December.
On 12 January 2008, he was named Premier League Player of the Month for December 2007.
The Paraguayan scored a 90th minute consolation goal for Blackburn in their 3–1 away loss to Liverpool on 13 April.
One week later, he scored in a 1–1 draw against Manchester United on 19 April.

In the following match, he went on to score in a 1–0 victory against Portsmouth and then two goals in a 3–1 win against Derby County which totalled to five goals in four consecutive matches.
Santa Cruz finished the season with 19 goals in 37 league appearances, finishing as the league's fourth top goal-scorer behind Cristiano Ronaldo (31 goals), Fernando Torres (24 goals) and Emmanuel Adebayor (24 goals), as Blackburn claimed seventh spot on the 2007–08 Premier League table with 58 points.
He was also voted as Blackburn's Player of the Season.
Santa Cruz agreed to a four-year deal with Blackburn on 28 July 2007. The club agreed to pay Bayern Munich £3.5 million for the player, where he was presented with the number nine shirt. The striker made his debut in the 2007–08 Premier League on the opening day of the season in a 2–1 away win against Middlesbrough on 11 August, where he was substituted onto the field for the injured Benni McCarthy in the 60th minute and after just three touches of the ball scored an equaliser in the 63rd minute. Two weeks later, he scored for Blackburn after 16 minutes in a 1–1 draw against Everton on 25 August. He celebrated his 26th birthday and his first full Rovers start when he scored in a 1–0 away first-leg win against MYPA in the 2007–08 UEFA Cup qualifying rounds on 16 August. He scored his first hat-trick for Blackburn in a 5–3 loss to Wigan Athletic on 15 December, Blackburn had been losing 3–0 before he had brought the sides level with his three goals. This hat-trick meant that he became the first player in over ten years in English football to score a hat-trick for the losing side, since Dwight Yorke's hat-trick on 30 September 1996 for Aston Villa in their 4–3 away loss to Newcastle United.
During the 2007–08 League Cup, he scored a brace in a 3–2 loss against Arsenal. Two weeks later, he scored a brace in a 2–2 draw against Manchester City on 27 December. On 12 January 2008, he was named Premier League Player of the Month for December 2007. The Paraguayan scored a 90th minute consolation goal for Blackburn in their 3–1 away loss to Liverpool on 13 April. One week later, he scored in a 1–1 draw against Manchester United on 19 April.
In the following match, he went on to score in a 1–0 victory against Portsmouth and then two goals in a 3–1 win against Derby County which totalled to five goals in four consecutive matches. Santa Cruz finished the season with 19 goals in 37 league appearances, finishing as the league's fourth top goal-scorer behind Cristiano Ronaldo (31 goals), Fernando Torres (24 goals) and Emmanuel Adebayor (24 goals), as Blackburn claimed seventh spot on the 2007–08 Premier League table with 58 points. He was also voted as Blackburn's Player of the Season.
Roque Santa Cruz