John Warden, Microsoft's lead attorney, passed the baton to another lawyer today. Maybe he should have kept it. On Day 10 of the Microsoft trial, Theodore Edelman, a young, raspy-voiced attorney for the company, attempted to discredit government witness Avadis "Avie" Tevanian Jr., senior vice-president for software engineering at Apple Computer. But Tevanian pretty much prevailed.

In some testy exchanges, Edelman tried to debunk Tevanian's allegations about Microsoft's use of market dominance against his company. While Microsoft scored early by getting Tevanian to admit to some inaccuracies in his written testimony, the Apple exec stuck to his guns about his core assertions. In the end, Edelman's wide-ranging cross-examination -- which included a handful of unproductive, hair-splitting digressions -- may have produced fewer points than Microsoft needed.

Curiously, Microsoft continues to question whether it is indeed a monopoly. Edelman asked Tevanian how he knew that Microsoft was dominant. The Apple witness, who cited a Dataquest study showing Microsoft with a 90% market share of the operating systems market, finally said: "I'm not a lawyer, but in this case, it seems so obvious that would be a true statement."

Edelman persevered with this theme later, pointing out the success of Apple's new iMac personal computer as evidence that PCs outfitted with non-Windows operating systems can still make a go of it. He also raised the budding success of the Linux operating system as further proof that other operating systems can thrive. To that, Tevanian replied: "In the great scheme of things, it's still a Windows monopoly. The fact we're getting some success doesn't change what I've said."

In another ongoing theme, Edelman briefly flicked at the point that Apple bundles free software with its new iMac -- perhaps in the same way that Microsoft bundles its Internet Explorer Web browser with Windows 95 and Windows 98. Edelman got Tevanian to concede that Apple does this because customers want it.

RHAPSODY'S BLUES. The Microsoft attorney fared best poking holes in Tevanian's assertion that Microsoft's Windows monopoly caused the failure of Apple's Rhapsody operating system. Tevanian said Apple pulled the plug on Rhapsody when software developers refused to rewrite Mac applications for Rhapsody because Apple would never sell enough of its new operating system in a Windows-dominated market. But Edelman asserted that the developers shied away from Rhapsody because of doubts about Apple's long-term financial viability. And he claimed Rhapsody was doomed by a poor product concept -- one requiring massive rewrites of applications. To bolster that argument, he showed a videotape of Apple's Steve Jobs at the company's May, 1998, Worldwide Developers Conference unveiling the well-received Mac OS 10, the successor product to Rhapsody that will not require as extensive applications upgrades.

Edelman tried with less success to undermine Tevanian's insistence that Microsoft tried to sabotage Apple's QuickTime multimedia software, which enables content makers to create online programming with video and audio capabilities on both Mac and Windows computers. Apple claims that users of Microsoft's Internet Explorer 4.0 browser who want to see content written on QuickTime often must have it played on Microsoft software instead of Apple software. And many times, it won't work. While Apple tried to get Microsoft to correct all the incompatibilities, Microsoft never did.

Apple's inability to solve the problem, Edelman claimed, was really the result of its refusal to sign a routine confidentiality agreement with Microsoft that would have enabled its programmers to see a beta version of the offending Microsoft software. To that Tevanian replied: "A beta version wouldn't tell us much -- just that it's broken." When Edelman asked him, "Don't you think 'sabotage' is a bit of an exaggeration?," the Apple witness replied: "It sounds fine to me."

NO NEW PLATFORMS? Tevanian stuck to his view that Microsoft sees QuickTime as a threat because the Apple software does not depend on a specific operating system to run it, and this type of software could render Windows obsolete. "We have a new emerging market based on [Web] content not on traditional word processor or spreadsheet [applications]," he says. "With QuickTime, we've engineered it in such a way it doesn't matter what the underlying operating system is. [Microsoft's] higher goal is to prevent someone from creating a new platform."

Lastly, Edelman tried to debunk Apple's assertion that Microsoft threatened to stop developing its popular Office application for the Mac unless Apple made Microsoft's Internet Explorer the default browser for Mac machines. He contended that a complex August, 1997, agreement between the two companies -- where Apple agreed to make IE its main browser -- was driven more by Microsoft's fear of a potential $1.2 billion patent infringement lawsuit from Apple. In this same agreement, Microsoft invested $150 million in Apple and agreed to cross-license Apple's patents. In the end, Edelman seemed unable to convince the judge, at the very least, that it's a cinch to change the Mac's browser from Microsoft's IE to Netscape's browser.

Surely, there'll be tougher things to convince the judge of before this trial ends. Microsoft's legal team will have do better than it did today.

By Cathy Yang in Washington