Markets are expected to open slightly lower on Tuesday morning, extending losses made the day before, as traders await a courtroom battle where the European Central Bank (ECB) is expected to defend its bond-buying programme. City sources predict the FTSE 100 will open down 16 points from yesterday's close of 6,400.Overnight, there were no surprises at the Bank of Japan's (BoJ) monetary policy meeting with the central bank leaving its aggressive easing plan in place. Following on from yesterday's upwards revision to first-quarter economic growth, the BoJ said that the economy "has been picking up".Focus now turns to the Eurozone this morning given the start of the two-day hearing into the legality of the ECB's Outright Monetary Transactions programme by the German constitutional court."ECB President Mario Draghi has gone to great lengths to calm German concerns about the program, going on German television yesterday pledging that there would be no transfer union, and that the ECB would not step into to save another European countries solvency," said Senior Market Analyst Michael Hewson from CMC Markets. "Even if one were to believe that, allowing another European country to go bankrupt would surely mean the breakup of the euro in its current form, and it is hard to believe that the ECB, or the EU for that matter would stand by and allow that to happen." Stocks to watchEngineering and project management group AMEC is to work with BP to provide the oil giant with environmental consulting services across its projects worldwide. The contract, for an unspecified amount, will run until 2017 and see AMEC provide services for all of BP's assets in the upstream, refining and marketing, alternative energy and shipping businesses.Energy services firm Wood Group has signed its first 'life-of-field' contract through an extension of work in the North Sea for AIM-listed Ithaca Energy worth $200m (£140m). Wood Group's PSN division (WGPSN), which began working with Ithaca in 2008, will continue to operate and deliver managed services to the Beatrice offshore platforms and Nigg onshore terminal until the end of their operating life.FTSE 250 office provider Workspace revealed a sharp increase in annual pre-tax profit and said it is ideally positioned to take advantage of the strength of the London economy. Pre-tax profit surged 58% to £76.4m for the year ended March 31st while EPRA net asset value per share increased by 13% to £3.48.