TORONTO - After falling victim to slow starts in each of the last two games, both losses, Raptors coach Dwane Casey hinted change could be on the way. Swell Flaske Salg . "Weve got to look at our starts," said Casey, the afternoon following a 90-83 defeat to Miami, one in which his team fell behind by nine in the first quarter. "Thats the second game in a row thats happened." Toronto allowed the Heat to shoot 52 per cent in the first quarter four days after the Nets shot 60 per cent in the opening 12 minutes of Tuesdays loss. Despite a second-half push, the Raptors failed to dig themselves out of an early-game hole in both contests, prompting Casey to suggest that a change could be imminent as soon as Sundays game, at home to Denver, or in Oakland against Golden State on Tuesday. "Whether its a lineup change or a change in personality," he continued, "weve got to look at something to start the game because we cant expend that much mental and physical energy to fight against all the teams were going against, and thats what its been the last couple of weeks." The Raptors - who used 22 different starting lineups last season, sixth most in the NBA - have started the same unit in each game to begin the campaign. After experiencing some success on the floor together - specifically on the defensive end - towards the end of last season, the group of Kyle Lowry, DeMar DeRozan, Rudy Gay, Amir Johnson and Jonas Valanciunas has underachieved through 15 contests this year. That unit - the Raptors most used, both this season and last - outscored opponents by 85 points when they were in the game together a year ago, starting 21 of the teams final 25 games. They ranked third in the NBA in defensive efficiency among five-man units that played a minimum of 300 minutes together (only the Spurs and Grizzlies starting fives had a better defensive rating). This season they are a minus-35, per NBA.com/stats, and are allowing opponents to shoot 52 per cent from the field. They have shared the floor for 229 minutes while the teams second most-utilized unit - Lowry, DeRozan, Gay and Johnson with Landry Fields - has played just 34 minutes together. As a team, Toronto has been least effective in the first and third quarters, with the starters playing the bulk of the teams minutes. The Raptors are a plus-three in the opening frame and minus-39 in the third. Their best quarter has been the fourth - a period in which the starters have rarely played together - where their plus-45 mark is third best in the NBA (behind only the Pacers and Thunder). "I think you have to look at the chemistry, skill set, what they bring to the table, a little bit of everything," Casey said of a possible change. "I dont question our guys fight. Its not that were not playing hard, its just not meshing together with the first group." Two starters who could be on the hot seat are Johnson and Valanciunas. Both frontcourt players logged fewer than 18 minutes in Fridays loss and have failed to meet lofty pre-season expectations overall. Tyler Hansbrough, who played 25 minutes and helped turn the game around in the second half with his physicality, earned praise from his coach following Saturdays practice and could be a candidate to replace either Johnson or Valanciunas in the event Casey decides to make a change. "It may be just a matter of time to let it go," Casey said. "Were still searching, like a lot of teams in the league are doing. Were not panicking but weve got to make sure we understand and we get the right group together." Toronto hosts the Denver Nuggets Sunday afternoon, concluding a season-high four-game homestand before heading out west next week. Swell Norge . Stiverne stopped Chris Arreola in the sixth round Saturday night, claiming the WBC heavyweight title belt vacated by Vitali Klitschko. Swell Flaske Norge . Last year, Matt Kuchar closed with a 4-under 68 to beat Kevin Chappell by two strokes for his second win of the 2013 season and sixth of his career. http://www.swellflaskenorge.com/ .com) - Nicolas Colsaerts fired an 11-under 60 on Thursday and grabbed a 3-stroke lead with the opening round of the Portugal Masters suspended by rain.Sebastian Vettel has thrown his support behind Maurizio Arrivabene after speculation in Italy suggested the Ferrari team boss could be fired at the end of the season. Italian publication Autosprint claimed Ferrari president Sergio Marchionne could replace Arrivabene as team principal with current technical director James Allison.Speculation at this weekends Spanish GP has also suggested Ferrari could be interested in recruiting Toro Rossos highly-rated technical boss James Key or Mercedes Aldo Costa, who worked for the Scuderia from 1995 to 2011. Arrivabene, a long-time commercial boss at Ferrari sponsor Philip Morris, was hired by Marchionne amid a senior management purge at the end of 2014 and oversaw their return to race-winning form last season.And Vettel has criticised the suggestion the 59-year-olds position could now be under threat.Hes the boss and is doing a very good job, the German said after Friday practice at Barcelona, where Ferrari ran Mercedes close.He is leading the team. Hes accessible for all the people, he spends a lot of time with the team, not just here but also [at Ferraris factory in] Maranello.I know there has been some rumours and some bull**** lately, but were very, very happy that hes with us and not with somebody else. James Allison (r) has been linked with replacing Arrivabene (l) With Ferrari yet to beat Mercedes in 2016, pressure has been growing on F1s most successful team.Marchionne told Sky F1 at last months Chinese GP the clock is on and earlier this week was quoted as saying I expect us to win shortly - starting with Spain.Mercedes are currently on a run of 10 consecutive race wins and the reigning champions will tie McLarens all-time F1 record with an 11th consecutive triumph in Spain. Ferrari have not beaten their rivals since last Septembers Singapore GP and their challenge at the start of this season has been hindered by reliability problems and on-track incidents.Who has the best driver line-up?But encouragingly for Ferraris prospects at Barcelona, the team split the Mercedes in Friday practice - leaving Vettel optimistic they can give Nico Rosberg and Lewis Hamilton mmore of a challenge this weekend. Swell Flaske Liberty. I dont think its ever too soon to start winning! he said in reference to Marchionnes pre-race remarks. We all know where we want to go, we want to win - thats why were here. Im not here to come second.But equally we know that our opposition at this stage is very strong. But this weekend coming should be a challenge for them. Ferrari have gone eight years without winning either world title and Marchionne has made clear only a championship victory will suffice in 2016.The Italian-Canadians recent comments suggest he is already running out of patience, but Vettel said the Ferrari presidents desire for success should be viewed as a positive, rather than a negative.First of all its great to see that our president cares, the German said. Hes really living with the team, he wants to help us where he can, and of course hes upset or disappointed as much as we are when something happens thats out of your hands and we are not finishing the race at all, or we are not finishing where we could have finished.So I see more the positives, rather than the pressure. Its good to have him behind us. Obviously I and the team speak to him more than the press, so this makes me actually quite confident that bit-by-bit things are going the right way.But, of course, we set out the target to win this year, we havent achieved that yet, so you have a fair point if you want to criticise us. Whatever happened lies behind us, we look ahead.Watch the Spanish GP live on Sky Sports F1. The race starts at 1pm on Sunday, with build-up underway at 11.30am. Or watch the race without a contract for £6.99 on NOW TV. Every race live in 2016 Sky Sports F1 brings you every race live in 2016. Fast and easy online upgrade - click here. Also See: Mercedes pip Ferrari in practice When is the Spanish GP on Sky? ' ' '