The broad market is following up an awful week with a not-so-good week for stocks.

And, once again, most of the selling is in the tech sector.

Some of the most prominent tech stocks are taking a serious beating in the tail-end of March, as the technology sector leaders that drove the broad market higher over the last two years suddenly get a bout of mean-reversion. One of the most glaring examples of the tech correction this week is Tesla Inc. (TSLA) .

Tesla is getting hammered lower following a bout of bad news surrounding self-driving cars.

The NTSB reported Tuesday that investigators are looking into a fatal crash of a Tesla Model X near Mountain View, California. That news comes as Nvidia Corp. (NVDA) announced that it was halting autonomous driving tests in the wake of a fatal crash involving an Uber self-driving car that killed a pedestrian in Arizona.

So, if you're picking out stocks to put in your retirement portfolio, does the recent rout in shares of Tesla provide an attractive buying opportunity? Or is this stock flashing its hazard lights?

For starters, it's crucial to remember that the characteristics that make a stock an attractive holding for your retirement portfolio aren't all that different from what makes a stock attractive to any other portfolio -- but for a more volatile name like Tesla, it's wise to size positions smaller than you would more stable stocks. And, from a short-term standpoint, what matters most is the technical setup in shares.

To figure out the price trajectory for shares of Tesla, we're turning to the chart for a technical look.

The good news is that you don't need to be an expert technical trader to figure out what's happening in shares of Tesla right now. The bad news is that it's not pretty.

Tesla had been holding onto a fairly well-defined uptrend in the final stretch of 2017 through the middle of this month, but that trendline support level got violated in dramatic fashion last week, clearing the way to the major downside moves we're seeing here.

In other words, the bad self-driving car news was the catalyst for shares of Tesla to tumble, but the technical failure last week has everything to do with the scale of the move.

Tesla actually began underperforming the market meaningfully back in mid-September, when relative strength rolled over and started its own downtrend. That series of lower highs in relative strength is our signal that shares are systematically underperforming the rest of the broad market in 2018.

So, should Tesla be on retirement investors' buy lists for 2018? The answer, at least right now, is no. Sellers are clearly in control of the price action right now.

That doesn't mean that Tesla will remain a stock to avoid forever, but we'd need to see buyers assert themselves and break the downtrends in price action and relative strength before it makes sense to take a position in shares. Caveat emptor.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.